Equity (Tables)

9 Months Ended

Sep. 30, 2011

Equity [Abstract]

Stockholders' Equity

										Accumulated
					Other					Other									Non-
	Common Stock				Paid-In		Retained			Comprehensive			Treasury Stock						Controlling
($ and shares in millions)	Shares		Par Value		Capital		Earnings			Loss			Shares			Cost			Interests			Total
Balance January 1, 2010		3,563	$	1,781	$	39,683	$	41,405		$	(2,767	)		454		$	(21,044	)	$	2,427		$	61,485
Net income attributable to Merck & Co., Inc.		—		—		—		1,393			—			—			—			—			1,393
Cash dividends declared on common stock		—		—		—		(3,552	)		—			—			—			—			(3,552	)
Mandatory conversion of 6% convertible preferred stock		4		2		132		—			—			—			—			—			134
Treasury stock shares purchased		—		—		—		—			—			47			(1,593	)		—			(1,593	)
Share-based compensation plans and other		10		5		742		—			—			(4	)		129			—			876
Other comprehensive loss		—		—		—		—			(723	)		—			—			—			(723	)
Net income attributable to noncontrolling interests		—		—		—		—			—			—			—			89			89
Distributions attributable to noncontrolling interests		—		—		—		—			—			—			—			(61	)		(61	)
Balance September 30, 2010		3,577	$	1,788	$	40,557	$	39,246		$	(3,490	)		497		$	(22,508	)	$	2,455		$	58,048
Balance January 1, 2011		3,577	$	1,788	$	40,701	$	37,536		$	(3,216	)		495		$	(22,433	)	$	2,429		$	56,805
Net income attributable to Merck & Co., Inc.		—		—		—		4,760			—			—			—			—			4,760
Cash dividends declared on common stock		—		—		—		(3,533	)		—			—			—			—			(3,533	)
Treasury stock shares purchased		—		—		—		—			—			41			(1,359	)		—			(1,359	)
Share-based compensation plans and other		—		—		16		—			—			(11	)		377			—			393
Other comprehensive income		—		—		—		—			503			—			—			—			503
Net income attributable to noncontrolling interests		—		—		—		—			—			—			—			89			89
Distributions attributable to noncontrolling interests		—		—		—		—			—			—			—			(62	)		(62	)
Balance September 30, 2011		3,577	$	1,788	$	40,717	$	38,763		$	(2,713	)		525		$	(23,415	)	$	2,456		$	57,596

Accumulated balances related to each component of other comprehensive income (loss)

     The accumulated balances related to each component of other comprehensive income (loss), net of taxes, were as follows:

													Accumulated
							Employee			Cumulative			Other
							Benefit			Translation			Comprehensive
($ in millions)	Derivatives			Investments			Plans			Adjustment			Income (Loss)
Balance January 1, 2010	$	(42	)	$	33		$	(2,469	)	$	(289	)	$	(2,767	)
Other comprehensive income (loss)		30			17			142			(912	)		(723	)
Balance at September 30, 2010	$	(12	)	$	50		$	(2,327	)	$	(1,201	)	$	(3,490	)
Balance January 1, 2011	$	41		$	31		$	(2,043	)	$	(1,245	)	$	(3,216	)
Other comprehensive income (loss)		(77	)		(11	)		59			532			503
Balance at September 30, 2011	$	(36	)	$	20		$	(1,984	)	$	(713	)	$	(2,713	)