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Joint ventures and other equity method affiliates.

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Partner payment for purchase of Asset Option.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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The number of units or percentage investment held by the managing member or general partner of the LLC or LP.

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Joint Ventures and Other Equity Method Affiliates (Details Textuals) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended		3 Months Ended	12 Months Ended		3 Months Ended
	Sep. 30, 2011	Sep. 30, 2011	Sep. 30, 2010	Jun. 30, 2010 AstraZeneca LP [Member]	Dec. 31, 2010 AstraZeneca LP [Member]	Dec. 31, 1998 AstraZeneca LP [Member]	Sep. 30, 2011 Johnson & Johnson Merck Consumer Pharmaceuticals Company [Member]
Joint Ventures and Other Equity Method Affiliates (Textuals) [Abstract]
Limited partner interest in AZLP						1.00%
General partner interest in AZLP						99.00%
Payment for purchase of Asset Option by Astra in connection with the 1998 restructuring						$ 443
Amount received by Merck for exercise of asset option			647		647
Gain on AstraZeneca asset option exercise			443	443
Percentage of ownership of JJMCP Joint Venture							50.00%
Cash Received by Merck on sale of interest in JJMCP							175
Gain on the disposition of the Company's interest in the JJMCP joint venture	$ 136	$ 136					$ 136