Cash and cash equivalents Inventories (excludes inventories of $674.3 in 2009 and $587.3 in 2008 classified in Other assets) Total current assets Property, Plant and Equipment, at cost, net of allowance for depreciation of $12,414.1 in 2009 and $12,128.6 in 2008 Total Assets Loans payable and current portion of long-term debt Total current liabilities Long-Term Debt Accumulated other comprehensive loss Other Intangibles, Net Total Merck & Co., Inc. stockholders' equity Total Liabilities and Stockholders' Equity Sales Research and development Restructuring costs Net Income Attributable to Merck & Co., Inc. Basic Earnings per Common Share Attributable to Merck & Co., Inc. Common Shareholders Earnings per Common Share Assuming Dilution Attributable to Merck & Co., Inc. Common Shareholders Materials and production Other (income) expense, net Taxes on Income Share-based compensation Net Cash Provided by Operating Activities Cash and Cash Equivalents at Beginning of Year Cash and Cash Equivalents at End of Period Net Increase in Cash and Cash Equivalents Effect of Exchange Rate Changes on Cash and Cash Equivalents Net Cash Provided by (Used by) Financing Activities Capital expenditures Net Cash Provided by Investing Activities Proceeds from sales of securities and other investments Payments on debt Retained earnings Noncontrolling Interests Short-term investments Accounts receivable (including non-trade receivables of $770.9 in 2009 and $871.2 in 2008) Investments Marketing and administrative Acquisitions of subsidiaries, net of cash acquired Net change in short-term borrowings Inventories classified in Other assets Balance Sheet [Abstract] Balance Sheet [Abstract] Balance Sheet. Current Liabilities Merck & Co., Inc. Stockholders' Equity Total Liabilities and Stockholders' Equity Noncontrolling Interest Minority Interest, Beginning Balance Minority Interest, Ending Balance Less treasury stock, at cost; 874,644,139 shares at June 30, 2009; 875,818,333 shares at December 31, 2008 Treasury Stock, Value, Beginning Balance Treasury Stock, Value, Ending Balance Common stock, one cent par value; Authorized - 5,400,000,000 shares; Issued - 2,983,508,675 shares Common Stock, Value, Total Common Stock, Value, Beginning Balance Common Stock, Value, Ending Balance Other paid-in capital Additional Paid in Capital, Common Stock, Beginning Balance Additional Paid in Capital, Common Stock, Ending Balance Retained earnings Retained Earnings (Accumulated Deficit), Beginning Balance Retained Earnings (Accumulated Deficit), Ending Balance Accumulated other comprehensive loss Accumulated Other Comprehensive Income (Loss), Net of Tax, Beginning Balance Accumulated Other Comprehensive Income (Loss), Net of Tax, Ending Balance Total Merck & Co., Inc. stockholders' equity Stockholders' Equity, Beginning Balance Stockholders' Equity, Ending Balance Less treasury stock, at cost; 874,644,139 shares at June 30, 2009; 875,818,333 shares at December 31, 2008 Current Assets Current Assets Statement of Income [Abstract] Statement of Income [Abstract] Statement of Income. Research and development Balance Sheet (Parenthetical) [Abstract] Balance Sheet (Parenthetical) [Abstract] Balance Sheet (Parenthetical). Inventories (excludes inventories of $776.1 in 2009 and $587.3 in 2008 classified in Other assets - - see Note 8) Property, Plant and Equipment, at cost, net of allowance for depreciation of $12,452.5 in 2009 and $12,128.6 in 2008 Property, Plant and Equipment, Net, Beginning Balance Property, Plant and Equipment, Net, Ending Balance Inventories classified in Other assets Statement of Cash Flows [Abstract] Statement of Cash Flows Abstract Statement of Cash Flow. Sales Materials and production Marketing and administrative Restructuring costs Equity income from affiliates Income (Loss) from Equity Method Investments, Total Other (income) expense, net Taxes on Income Net Income Attributable to Merck & Co., Inc. Basic Earnings per Common Share Attributable to Merck & Co., Inc. Common Shareholders Earnings per Common Share Assuming Dilution Attributable to Merck & Co., Inc. Common Shareholders Dividends Declared per Common Share Dividends Declared per Common Share Cash and cash equivalents Short-term investments Accounts receivable (including non-trade receivables of $629.9 in 2009 and $871.2 in 2008) Deferred income taxes and other current assets Deferred income taxes and other current assets Total current assets Investments Goodwill Goodwill Goodwill, Beginning Balance Goodwill, Ending Balance Other Intangibles, Net Other Assets Other Assets Total Assets Loans payable and current portion of long-term debt Total current liabilities Long-Term Debt Gain on distribution from AstraZeneca LP Dividends and distributions from equity affiliates Deferred income taxes Deferred Income Tax Expense (Benefit), Total Share-based compensation Net changes in assets and liabilities Net changes in assets and liabilities Capital expenditures Acquisitions of subsidiaries, net of cash acquired Proceeds from sales of securities and other investments Distribution from AstraZeneca LP Other Other Net Cash Used by Investing Activities Net change in short-term borrowings Payments on debt Purchases of treasury stock Dividends paid to stockholders Proceeds from exercise of stock options Other Other Net Cash Used by Financing Activities Effect of Exchange Rate Changes on Cash and Cash Equivalents Net Increase in Cash and Cash Equivalents Cash Flows from Operating Activities Cash Flows from Operating Activities Cash Flows from Investing Activities Cash Flows from Investing Activities Cash Flows from Financing Activities Cash Flows from Financing Activities Document and Company Information [Abstract] Document and Company Information [Abstract] Document and Company Information. Basis of Presentation [Abstract] Basis of Presentation [Abstract] Basis of Presentation. Merger Agreement with Schering-Plough Corporation [Abstract] Merger Agreement with Schering-Plough Corporation [Abstract] Merger Agreement. Merger Agreement with Schering-Plough Corporation Merger Agreement Text Block Merger Agreement. Restructuring [Abstract] Restructuring [Abstract] Restructuring. Research Collaborations, Acquisitions and License Agreements [Abstract] Research Collaborations, Acquisitions and License Agreements [Abstract] Research Collaborations, Acquisitions and License Agreements. Collaborative Arrangements [Abstract] Collaborative Arrangements [Abstract] Collaborative Arrangements. Collaborative Arrangements Restructuring Fair Value Measurements [Abstract] Fair Value Measurements [Abstract] Fair Value Measurements. Derivative Instruments and Hedging Activities [Abstract] Derivative Instruments and Hedging Activities [Abstract] Derivative Instruments and Hedging Activities. Derivative Instruments and Hedging Activities Inventories [Abstract] Inventories [Abstract] Inventories. Inventories Joint Ventures and Other Equity Method Affiliates [Abstract] Joint Ventures and Other Equity Method Affiliates [Abstract] Joint Ventures and Other Equity Method Affiliates. Contingencies [Abstract] Contingencies [Abstract] Contingencies. Contingencies Stockholders' Equity Share-Based Compensation [Abstract] Share-Based Compensation [Abstract] Share-Based Compensation. Pension and Other Postretirement Benefit Plans [Abstract] Pension and Other Postretirement Benefit Plans [Abstract] Pension and Other Postretirement Benefit Plans. Share-Based Compensation Other (Income) Expense, Net [Abstract] Other (Income) Expense, Net [Abstract] Other (Income) Expense, Net. Other (Income) Expense, Net Taxes on Income [Abstract] Taxes on Income [Abstract] Taxes on Income. Taxes on Income Earnings Per Share [Abstract] Earnings Per Share [Abstract] Segment Reporting [Abstract] Segment Reporting [Abstract] Segment Reporting. Segment Reporting Income taxes payable Trade accounts payable Accounts Payable, Current, Total Total equity Total Equity Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Beginning Balance Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Ending Balance Less: Net Income Attributable to Noncontrolling Interests Less: Net Income Attributable to Noncontrolling Interests Net income Net Income Costs, Expenses and Other Costs and Expenses Nonoperating Income Expense Abstract Costs and Expenses Nonoperating Income Expense. Non-trade receivables Non-trade receivables Depreciation and amortization Depreciation and amortization Other Other Decrease in restricted assets Decrease in restricted assets Increase/Decrease in restricted cash investments. Allowance for depreciation Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment, Total Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment, Beginning Balance Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment, Ending Balance Common stock, par value Common stock, shares authorized Common stock, shares issued Common Stock, Shares, Issued, Total Treasury stock, shares Treasury Stock, Shares, Beginning Balance Treasury Stock, Shares, Ending Balance Assets Liabilities and Stockholders' Equity Accrued and other current liabilities Accrued And Other Current Liabilities Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent, salaries, and utilities. For classified balance sheets, used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer); for unclassified balance sheets, used to reflect the total liabilities (regardless of due date) and Aggregate carrying amount, as of the balance sheet date, of current obligations not separately disclosed in the balance sheet due to materiality considerations. Current liabilities are expected to be paid within one year (or the normal operating cycle, if longer). Purchases of securities and other investments Purchases of securities and other investments The cash outflow associated with the purchase of all investments (debt, security, other) during the period and the cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence. Deferred Income Taxes and Noncurrent Liabilities Deferred Income Taxes and Noncurrent Liabilities Represents the noncurrent portion of deferred tax liabilities, which result from applying the applicable tax rate to net taxable temporary differences pertaining to each jurisdiction to which the entity is obligated to pay income tax. A noncurrent taxable temporary difference is a difference between the tax basis and the carrying amount of a noncurrent asset or liability in the financial statements prepared in accordance with generally accepted accounting principles. In a classified statement of financial position, an enterprise shall separate deferred tax liabilities and assets into a current amount and a noncurrent amount. Deferred tax liabilities and assets shall be classified as current or noncurrent based on the classification of the related asset or liability for financial reporting. A deferred tax liability or asset that is not related to an asset or liability for financial reporting, including deferred tax assets related to carryforwards, shall be classified according to the expected reversal date of the temporary difference. Aggregate carrying amount, as of the balance sheet date, of noncurrent obligations not separately disclosed in the balance sheet due to materiality considerations. Noncurrent liabilities are expected to be paid after one year (or the normal operating cycle, if longer). Deferred Income Taxes and Noncurrent Liabilities Dividends payable Statement of Cash Flows [Abstract] Purchases Securities And Other Investments Increase Decrease In Restricted Cash Investments Net Income (Loss) Attributable to Parent Earnings Per Share, Basic Earnings Per Share, Diluted Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Liabilities and Stockholders' Equity Inventory, Net Inventory, Noncurrent Stockholders' equity before deduction for treasury stock Stockholders Equity Before Deduction For Treasury Stock Stockholders' equity before deduction for treasury stock. Adjustments to reconcile net income to net cash provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Total Costs, Expenses and Other Total Costs Expenses And Other Total Costs, Expenses and Other. Income Before Taxes Income Before Taxes Sum of operating profit and nonoperating income (expense) before income taxes, extraordinary items, cumulative effects of changes in accounting principles, and noncontrolling interest. Basis of Presentation Basis Of Presentation And Description Of New Accounting Pronouncements Not Yet Adopted Text Block Basis of Presentation and Description of New Accounting Pronouncements Not Yet Adopted. Research Collaborations, Acquisitions and License Agreements Research Collaborations Acquisitions And License Agreements Text Block Research Collaborations Acquisitions and License Agreements. Fair Value Measurements Fair Value, Measurement Inputs, Disclosure [Text Block] Joint Ventures and Other Equity Method Affiliates Equity Method Investments Disclosure [Text Block] Debt and Financial Instruments Debt And Financial Instruments Disclosure Text Block Debt and Financial Instruments. Pension and Other Postretirement Benefits Plans Pension and Other Postretirement Benefits Disclosure [Text Block] Earnings Per Share Earnings Per Share [Text Block] Debt and Financial Instrument [Abstract] Debt and Financial Instrument [Abstract] Debt and Financial Instruments. Total Costs, Expenses and Other Assets Payments on debt Repayments of Long-term Debt Purchases of treasury stock Payments for Repurchase of Common Stock Dividends paid to stockholders Payments of Dividends, Common Stock Capital expenditures Payments to Acquire Productive Assets Purchases of securities and other investments Acquisitions of subsidiaries, net of cash acquired Payments to Acquire Businesses, Net of Cash Acquired Other Payments for (Proceeds from) Other Investing Activities Equity income from affiliates Income (Loss) from Equity Method Investments Other (income) expense, net Other Nonoperating Income (Expense) Income Loss From Continuing Operations Before Income Taxes Minority Interests Statement of Cash Flows [Abstract] Statement Of Cash Flow [Abstract] Merger Agreement with Schering-Plough Corporation [Abstract] Share Based Compensations [Abstract] Earnings Per Share [Abstract] Merger Agreement with Schering-Plough Corporation [Abstract] Receivables, Net, Current Property, Plant and Equipment, Net Treasury Stock, Value Stockholders' Equity Attributable to Noncontrolling Interest Net Income (Loss) Attributable to Noncontrolling Interest Proceeds from issuance of debt, net Proceeds from Issuance of Long-term Debt, Total Proceeds from Issuance of Long-term Debt Net Cash Provided by (Used in) Financing Activities Common Stock, Value, Issued Document And Company Information [Abstract] Entity Registrant Name Entity Central Index Key Document Type Document Period End Date Amendment Flag Amendment Description Current Fiscal Year End Date Entity Well-known Seasoned Issuer Entity Voluntary Filers Entity Current Reporting Status Entity Filer Category Entity Public Float Entity Common Stock, Shares Outstanding Statement [Table] Statement [Line Items] Revenues Cost of Goods Sold Selling, General and Administrative Expense Research and Development Expense Restructuring Charges Income Tax Expense (Benefit) Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Common Stock, Dividends, Per Share, Declared Statement, Scenario [Axis] Scenario, Unspecified [Domain] Assets [Abstract] Assets, Current [Abstract] Cash and Cash Equivalents, at Carrying Value Marketable Securities, Current Other Assets, Current Assets, Current Marketable Securities, Noncurrent Goodwill Intangible Assets, Net (Excluding Goodwill) Other Assets, Noncurrent Liabilities and Stockholders' Equity [Abstract] Liabilities, Current [Abstract] Debt, Current Accounts Payable, Current Accrued Income Taxes, Current Dividends Payable, Current Liabilities, Current Long-term Debt, Excluding Current Maturities Stockholders' Equity [Abstract] Additional Paid in Capital, Common Stock Retained Earnings (Accumulated Deficit) Accumulated Other Comprehensive Income (Loss), Net of Tax Stockholders' Equity Attributable to Parent Scenario, Actual [Member] Scenario, Adjustment [Member] Scenario, Forecast [Member] Scenario, Plan [Member] Scenario, Previously Reported [Member] Nontrade Receivables Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Common Stock, Par or Stated Value Per Share Common Stock, Shares Authorized Common Stock, Shares, Issued Treasury Stock, Shares Net Cash Provided by (Used in) Operating Activities [Abstract] Gain (Loss) on Sale of Equity Method Investments Equity Method Investment, Dividends or Distributions Depreciation, Depletion and Amortization Deferred Income Tax Expense (Benefit) Share-based Compensation Adjustments, Noncash Items, to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities, Other Increase (Decrease) in Other Operating Assets and Liabilities, Net Net Cash Provided by (Used in) Operating Activities Net Cash Provided by (Used in) Investing Activities [Abstract] Proceeds from Sale, Maturity and Collections of Investments Proceeds from Sale of Equity Method Investments Net Cash Provided by (Used in) Investing Activities Net Cash Provided by (Used in) Financing Activities [Abstract] Proceeds from (Repayments of) Short-term Debt, Maturing in Three Months or Less Proceeds from Stock Options Exercised Proceeds from (Payments for) Other Financing Activities Effect of Exchange Rate on Cash and Cash Equivalents Cash and Cash Equivalents, Period Increase (Decrease) Merger Agreement [Abstract] Restructuring and Related Activities Disclosure [Text Block] Collaborative Arrangement Disclosure [Text Block] Derivative Instruments and Hedging Activities Disclosure [Text Block] Inventory Disclosure [Text Block] Commitments and Contingencies Disclosure [Text Block] Stockholders' Equity Note Disclosure [Text Block] Disclosure of Compensation Related Costs, Share-based Payments [Text Block] Other Income and Other Expense Disclosure [Text Block] Income Tax Disclosure [Text Block] Segment Reporting Disclosure [Text Block]