CONSOLIDATED STATEMENTS OF CASH FLOWS UNAUDITED (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Statement of Cash Flows [Abstract]
Net income (loss)	$ 194,874	$ 86,924	$ (106,109)
Loss from discontinued operations	0	74,608	120,573
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation expense	51,932	47,053	46,096
Amortization expense	84,009	86,079	104,450
Write Off Of Deferred Debt Issuance Cost	12,466	6,012	6,636
Debt redemption tender premium	0	(19,582)	(7,591)
Goodwill and Intangible Asset Impairment	0	0	22,884
Benefit Plan Termination and Related Costs	0	0	25,187
Losses on Extinguishment of Debt	35,092	0	25,552
Deferred Income Tax Expense (Benefit)	95,742	62,909	22,952
Changes in assets and liabilities, net of effects from acquisition and divestiture of businesses:
Accounts receivable and unbilled receivables, net of provision for doubtful accounts	80,080	100,584	198,863
Inventories	37,736	4,994	(34,676)
Other current and noncurrent assets	17,110	120,360	38,966
Accounts payable	(69,423)	26,351	(44,638)
Accrued employee compensation	12,476	1,595	21,451
Current and noncurrent liabilities	(7,610)	(48,488)	(71,693)
Net cash flows from operating activities of continuing operations	544,484	549,399	368,903
Net cash flows from operating activities of discontinued operations	0	623	(288)
Net cash flows from operating activities	544,484	550,022	368,615
Cash flows from investing activities:
Acquisition of businesses, net of cash received	(34,873)	(101,933)	(111,812)
Divestiture of business, net	19,207	13,099	0
Capital expenditures	(99,920)	(62,806)	(23,517)
Payments to Acquire Marketable Securities	(25,018)	0	0
Benefit Plan Termination and Other Related Costs	1,326	(275)	11,082
Other	(56)	(2,874)	(1,259)
Net cash flows used in investing activities of continuing operations	(139,334)	(154,789)	(125,506)
Net cash flows used in investing activities of discontinued operations	0	(622)	(546)
Net cash flows used in investing activities	(139,334)	(155,411)	(126,052)
Cash flows from financing activities:
Payments on Term A loan	(24,688)	(5,625)	(125,000)
Proceeds from long term borrowings and obligations	425,000	600,000	975,000
Payments on long-term borrowings and obligations	(453,573)	(777,609)	(726,533)
Option indexed to issuers equity cash paid	(48,126)	0	0
Fees paid for financing arrangements	(7,566)	(13,780)	(33,249)
Increase (decrease) in cash overdraft balance	(14,927)	11,674	18,221
Payments for Omnicare common stock repurchase (Note 2)	(388,968)	(140,127)	(100,942)
Proceeds (payments) for stock awards and exercise of stock options, net of stock tendered in payment	24,951	30,712	(13,989)
Dividends paid	(45,214)	(17,217)	(12,839)
Other	1,912	3,140	(5,289)
Net cash flows used in financing activities	(531,199)	(308,832)	(24,620)
Net increase (decrease) in cash and cash equivalents	(126,049)	85,779	217,943
Less increase in cash and cash equivalents of discontinued operations	0	1	(834)
Increase (decrease) in cash and cash equivalents of continuing operations	(126,049)	85,778	218,777
Cash and cash equivalents at beginning of period	580,262	494,484	275,707
Cash and cash equivalents at end of period	$ 454,213	$ 580,262	$ 494,484