Guarantor Subsidiaries (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
Summary Consolidating Statements of Income [Abstract]
Net sales	$ 1,525,003	$ 1,593,068
Cost of sales	1,154,179	1,224,968
Gross profit	370,824	368,100
Selling, general and administrative expenses	201,826	200,124
Provision for doubtful accounts	24,226	24,431
Settlements, litigations and other related charges	22,619	7,203
Other miscellaneous charges	4,006	11,512
Operating income (loss)	118,147	124,830
Interest expense, net of investment income	(29,459)	(30,834)
Income before income taxes	88,688	93,996
Income tax (benefit) expense	34,334	38,257
Equity of net income (loss) of subsidiaries	0	0
Income (Loss) from Continuing Operations, Including Portion Attributable to Noncontrolling Interest	54,354	55,739
Comprehensive income (loss)	54,330	56,161
ASSETS
Cash and Cash Equivalents, at Carrying Value	509,818	622,177
Restricted Cash and Investments, Current	5		1,066
Accounts Receivable, Net, Current	840,383		857,052
Inventory, Net	382,658		385,698
Deferred Tax Assets, Net of Valuation Allowance, Current	115,785		136,186
Other Assets, Current	279,476		254,644
Assets, Current	2,128,125		2,088,859
Property, Plant and Equipment, Net	292,794		282,660
Goodwill	4,256,959		4,256,959
Intangible Assets, Net (Excluding Goodwill)	187,263		196,873
Other Assets, Noncurrent	147,211		163,913
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	0		0
Assets	7,012,352		6,989,264
LIABILITIES AND STOCKHOLDERS' EQUITY
Liabilities, Current	672,175		482,014
Long-term Debt, Excluding Current Maturities	1,817,991		2,030,030
Deferred income tax liabilities	910,040		914,660
Other noncurrent liabilities	61,909		56,848
Stockholders' equity	3,550,237		3,505,712
Total liabilities and stockholders' equity	7,012,352		6,989,264
Cash flows from operating activities:
Net cash flows (used in) from operating activities	108,895	100,417
Cash flows from investing activities:
Acquisition of businesses, net of cash received	0	(563)
Capital expenditures	(23,129)	(20,239)
Other Investing Activities	854	512
Net cash flows used in investing activities	(22,275)	(20,290)
Cash flows from financing activities:
Payments on Term Loans	(5,313)	(6,587)
Payments on long-term borrowings and obligations	(1,684)	0
Proceeds from (Repayments of) Bank Overdrafts	(9,774)	(3,151)
Payments for Omnicare common stock repurchase	(302)	(22,328)
Dividends paid	(14,479)	(7,825)
Proceeds from (payments for) Other Financing Activities including disc Ops	537	1,679
Net Cash Provided by (Used in) Financing Activities	(31,015)	(38,212)
Net increase (decrease) in cash and cash equivalents	55,605	41,915
Cash and cash equivalents at beginning of period	454,213	580,262
Cash and cash equivalents at end of period	509,818	622,177
Parent Company [Member]
Summary Consolidating Statements of Income [Abstract]
Net sales	0	0
Cost of sales	0	0
Gross profit	0	0
Selling, general and administrative expenses	1,006	1,003
Provision for doubtful accounts	0	0
Settlements, litigations and other related charges	0	0
Other miscellaneous charges	0	0
Operating income (loss)	(1,006)	(1,003)
Interest expense, net of investment income	(28,991)	(30,388)
Income before income taxes	(29,997)	(31,391)
Income tax (benefit) expense	(11,546)	(12,086)
Equity of net income (loss) of subsidiaries	72,805	75,044
Income (Loss) from Continuing Operations, Including Portion Attributable to Noncontrolling Interest	54,354	55,739
Comprehensive income (loss)	54,330	56,161
ASSETS
Cash and Cash Equivalents, at Carrying Value	437,264	505,499
Restricted Cash and Investments, Current	0		0
Accounts Receivable, Net, Current	0		0
Inventory, Net	0		0
Deferred Tax Assets, Net of Valuation Allowance, Current	67		0
Other Assets, Current	2,105		1,765
Assets, Current	439,436		385,439
Property, Plant and Equipment, Net	0		0
Goodwill	0		0
Intangible Assets, Net (Excluding Goodwill)	0		0
Other Assets, Noncurrent	68,243		75,336
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	5,454,351		5,453,702
Assets	5,962,030		5,914,477
LIABILITIES AND STOCKHOLDERS' EQUITY
Liabilities, Current	271,877		60,454
Long-term Debt, Excluding Current Maturities	1,801,588		2,012,807
Deferred income tax liabilities	338,328		335,504
Other noncurrent liabilities			0
Stockholders' equity	3,550,237		3,505,712
Total liabilities and stockholders' equity	5,962,030		5,914,477
Cash flows from operating activities:
Net cash flows (used in) from operating activities	(3,365)	3,153
Cash flows from investing activities:
Acquisition of businesses, net of cash received		0
Capital expenditures	0	0
Other Investing Activities	(227)	0
Net cash flows used in investing activities	(227)	0
Cash flows from financing activities:
Payments on Term Loans	(5,313)	(6,587)
Payments on long-term borrowings and obligations	(1,684)
Proceeds from (Repayments of) Bank Overdrafts	(10,900)	290
Payments for Omnicare common stock repurchase	(302)	(22,328)
Dividends paid	(14,479)	(7,825)
Proceeds from (payments for) Other Financing Activities including disc Ops	89,860	78,543
Net Cash Provided by (Used in) Financing Activities	57,182	42,093
Net increase (decrease) in cash and cash equivalents	53,590	45,246
Cash and cash equivalents at beginning of period	383,674	460,253
Cash and cash equivalents at end of period	437,264	505,499
Guarantor Subsidiaries [Member] | Convertible Senior Debentures [Member]
Summary Consolidating Statements of Income [Abstract]
Net sales	0	0
Cost of sales	0	0
Gross profit	0	0
Selling, general and administrative expenses	399	322
Provision for doubtful accounts	0	0
Settlements, litigations and other related charges	0	0
Other miscellaneous charges	0	0
Operating income (loss)	(399)	(322)
Interest expense, net of investment income	0	0
Income before income taxes	(399)	(322)
Income tax (benefit) expense	(154)	(124)
Equity of net income (loss) of subsidiaries	0	0
Income (Loss) from Continuing Operations, Including Portion Attributable to Noncontrolling Interest	(245)	(198)
Comprehensive income (loss)	(245)	(198)
ASSETS
Cash and Cash Equivalents, at Carrying Value	0	0
Restricted Cash and Investments, Current	0		0
Accounts Receivable, Net, Current	201		204
Inventory, Net	0		0
Deferred Tax Assets, Net of Valuation Allowance, Current	0		0
Other Assets, Current	0		0
Assets, Current	201		204
Property, Plant and Equipment, Net	22		22
Goodwill	0		0
Intangible Assets, Net (Excluding Goodwill)	0		0
Other Assets, Noncurrent	19		19
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	0		0
Assets	242		245
LIABILITIES AND STOCKHOLDERS' EQUITY
Liabilities, Current	54		54
Long-term Debt, Excluding Current Maturities	0		0
Deferred income tax liabilities	0		0
Other noncurrent liabilities	0		0
Stockholders' equity	188		191
Total liabilities and stockholders' equity	242		245
Cash flows from operating activities:
Net cash flows (used in) from operating activities	0	0
Cash flows from investing activities:
Acquisition of businesses, net of cash received		0
Capital expenditures	0	0
Other Investing Activities	0	0
Net cash flows used in investing activities	0	0
Cash flows from financing activities:
Payments on Term Loans	0	0
Payments on long-term borrowings and obligations	0
Proceeds from (Repayments of) Bank Overdrafts	0	0
Payments for Omnicare common stock repurchase	0	0
Dividends paid	0	0
Proceeds from (payments for) Other Financing Activities including disc Ops	0	0
Net Cash Provided by (Used in) Financing Activities	0	0
Net increase (decrease) in cash and cash equivalents	0	0
Cash and cash equivalents at beginning of period	0	0
Cash and cash equivalents at end of period	0	0
Guarantor Subsidiaries [Member] | Guaranteed Senior Notes Payable [Member]
Summary Consolidating Statements of Income [Abstract]
Net sales	1,492,388	1,557,403
Cost of sales	1,135,340	1,201,149
Gross profit	357,048	356,254
Selling, general and administrative expenses	196,036	188,723
Provision for doubtful accounts	23,746	23,966
Settlements, litigations and other related charges	22,619	7,203
Other miscellaneous charges	4,006	11,512
Operating income (loss)	110,641	124,850
Interest expense, net of investment income	(290)	(283)
Income before income taxes	110,351	124,567
Income tax (benefit) expense	42,672	47,755
Equity of net income (loss) of subsidiaries	0	0
Income (Loss) from Continuing Operations, Including Portion Attributable to Noncontrolling Interest	67,679	76,812
Comprehensive income (loss)	67,679	76,812
ASSETS
Cash and Cash Equivalents, at Carrying Value	62,790	97,581
Restricted Cash and Investments, Current	5		1,066
Accounts Receivable, Net, Current	834,286		849,753
Inventory, Net	375,390		379,448
Deferred Tax Assets, Net of Valuation Allowance, Current	116,782		137,736
Other Assets, Current	267,048		248,833
Assets, Current	1,656,301		1,675,148
Property, Plant and Equipment, Net	286,266		276,056
Goodwill	4,228,135		4,219,900
Intangible Assets, Net (Excluding Goodwill)	184,454		193,852
Other Assets, Noncurrent	83,903		93,508
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	0		0
Assets	6,439,059		6,458,464
LIABILITIES AND STOCKHOLDERS' EQUITY
Liabilities, Current	609,959		587,025
Long-term Debt, Excluding Current Maturities	16,403		17,223
Deferred income tax liabilities	553,663		559,405
Other noncurrent liabilities	76,661		68,161
Stockholders' equity	5,182,373		5,226,650
Total liabilities and stockholders' equity	6,439,059		6,458,464
Cash flows from operating activities:
Net cash flows (used in) from operating activities	114,407	94,417
Cash flows from investing activities:
Acquisition of businesses, net of cash received		(563)
Capital expenditures	(22,813)	(19,432)
Other Investing Activities	1,081	513
Net cash flows used in investing activities	(21,732)	(19,482)
Cash flows from financing activities:
Payments on Term Loans	0	0
Payments on long-term borrowings and obligations	0
Proceeds from (Repayments of) Bank Overdrafts	1,126	(3,441)
Payments for Omnicare common stock repurchase	0	0
Dividends paid	0	0
Proceeds from (payments for) Other Financing Activities including disc Ops	(89,323)	(75,699)
Net Cash Provided by (Used in) Financing Activities	(88,197)	(79,140)
Net increase (decrease) in cash and cash equivalents	4,478	(4,205)
Cash and cash equivalents at beginning of period	58,312	101,786
Cash and cash equivalents at end of period	62,790	97,581
Non-Guarantor Subsidiaries [Member] | Convertible Senior Debentures [Member]
Summary Consolidating Statements of Income [Abstract]
Net sales	1,525,003	1,593,068
Cost of sales	1,154,179	1,224,968
Gross profit	370,824	368,100
Selling, general and administrative expenses	200,421	198,799
Provision for doubtful accounts	24,226	24,431
Settlements, litigations and other related charges	22,619	7,203
Other miscellaneous charges	4,006	11,512
Operating income (loss)	119,552	126,155
Interest expense, net of investment income	(468)	(446)
Income before income taxes	119,084	125,709
Income tax (benefit) expense	46,034	50,467
Equity of net income (loss) of subsidiaries	0	0
Income (Loss) from Continuing Operations, Including Portion Attributable to Noncontrolling Interest	73,050	75,242
Comprehensive income (loss)	73,050	75,242
ASSETS
Cash and Cash Equivalents, at Carrying Value	72,554	116,678
Restricted Cash and Investments, Current	5		1,066
Accounts Receivable, Net, Current	840,383		857,052
Inventory, Net	382,658		385,698
Deferred Tax Assets, Net of Valuation Allowance, Current	115,718		137,736
Other Assets, Current	277,371		252,879
Assets, Current	1,688,689		1,704,970
Property, Plant and Equipment, Net	292,772		282,638
Goodwill	4,256,959		4,256,959
Intangible Assets, Net (Excluding Goodwill)	187,263		196,873
Other Assets, Noncurrent	78,949		88,558
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	0		0
Assets	6,504,632		6,529,998
LIABILITIES AND STOCKHOLDERS' EQUITY
Liabilities, Current	400,445		421,710
Long-term Debt, Excluding Current Maturities	16,403		17,223
Deferred income tax liabilities	571,712		580,706
Other noncurrent liabilities	61,909		56,848
Stockholders' equity	5,454,163		5,453,511
Total liabilities and stockholders' equity	6,504,632		6,529,998
Cash flows from operating activities:
Net cash flows (used in) from operating activities	112,260	97,264
Cash flows from investing activities:
Acquisition of businesses, net of cash received		(563)
Capital expenditures	(23,129)	(20,239)
Other Investing Activities	1,081	512
Net cash flows used in investing activities	(22,048)	(20,290)
Cash flows from financing activities:
Payments on Term Loans	0	0
Payments on long-term borrowings and obligations	0
Proceeds from (Repayments of) Bank Overdrafts	1,126	(3,441)
Payments for Omnicare common stock repurchase	0	0
Dividends paid	0	0
Proceeds from (payments for) Other Financing Activities including disc Ops	(89,323)	(76,864)
Net Cash Provided by (Used in) Financing Activities	(88,197)	(80,305)
Net increase (decrease) in cash and cash equivalents	2,015	(3,331)
Cash and cash equivalents at beginning of period	70,539	120,009
Cash and cash equivalents at end of period	72,554	116,678
Non-Guarantor Subsidiaries [Member] | Guaranteed Senior Notes Payable [Member]
Summary Consolidating Statements of Income [Abstract]
Net sales	32,615	35,665
Cost of sales	18,839	23,819
Gross profit	13,776	11,846
Selling, general and administrative expenses	4,784	10,398
Provision for doubtful accounts	480	465
Settlements, litigations and other related charges	0	0
Other miscellaneous charges	0	0
Operating income (loss)	8,512	983
Interest expense, net of investment income	(178)	(163)
Income before income taxes	8,334	820
Income tax (benefit) expense	3,208	2,588
Equity of net income (loss) of subsidiaries	0	0
Income (Loss) from Continuing Operations, Including Portion Attributable to Noncontrolling Interest	5,126	(1,768)
Comprehensive income (loss)	5,126	(1,768)
ASSETS
Cash and Cash Equivalents, at Carrying Value	9,764	19,097
Restricted Cash and Investments, Current	0		0
Accounts Receivable, Net, Current	244,778		197,370
Inventory, Net	7,268		6,250
Deferred Tax Assets, Net of Valuation Allowance, Current	0		0
Other Assets, Current	21,148		14,871
Assets, Current	282,958		230,718
Property, Plant and Equipment, Net	6,528		6,604
Goodwill	28,824		37,059
Intangible Assets, Net (Excluding Goodwill)	2,809		3,021
Other Assets, Noncurrent	14,817		11,382
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	0		0
Assets	335,936		288,784
LIABILITIES AND STOCKHOLDERS' EQUITY
Liabilities, Current	39,845		35,431
Long-term Debt, Excluding Current Maturities	5,000		5,000
Deferred income tax liabilities	19,113		21,301
Other noncurrent liabilities	0		0
Stockholders' equity	271,978		227,052
Total liabilities and stockholders' equity	335,936		288,784
Cash flows from operating activities:
Net cash flows (used in) from operating activities	(2,147)	2,847
Cash flows from investing activities:
Acquisition of businesses, net of cash received		0
Capital expenditures	(316)	(807)
Other Investing Activities	0	(1)
Net cash flows used in investing activities	(316)	(808)
Cash flows from financing activities:
Payments on Term Loans	0	0
Payments on long-term borrowings and obligations	0
Proceeds from (Repayments of) Bank Overdrafts	0	0
Payments for Omnicare common stock repurchase	0	0
Dividends paid	0	0
Proceeds from (payments for) Other Financing Activities including disc Ops	0	(1,165)
Net Cash Provided by (Used in) Financing Activities	0	(1,165)
Net increase (decrease) in cash and cash equivalents	(2,463)	874
Cash and cash equivalents at beginning of period	12,227	18,223
Cash and cash equivalents at end of period	9,764	19,097
Consolidating, Eliminating Adjustments [Member]
Summary Consolidating Statements of Income [Abstract]
Net sales	0	0
Cost of sales	0	0
Gross profit	0	0
Selling, general and administrative expenses	0	0
Provision for doubtful accounts	0	0
Settlements, litigations and other related charges	0	0
Other miscellaneous charges	0	0
Operating income (loss)	0	0
Interest expense, net of investment income	0	0
Income before income taxes	0	0
Income tax (benefit) expense	0	0
Equity of net income (loss) of subsidiaries	(72,805)	(75,044)
Income (Loss) from Continuing Operations, Including Portion Attributable to Noncontrolling Interest	(72,805)	(75,044)
Comprehensive income (loss)	(72,805)	(75,044)
Consolidating, Eliminating Adjustments [Member] | Convertible Senior Debentures [Member]
ASSETS
Cash and Cash Equivalents, at Carrying Value	0		0
Restricted Cash and Investments, Current	0		0
Accounts Receivable, Net, Current	(201)		(204)
Inventory, Net	0		0
Deferred Tax Assets, Net of Valuation Allowance, Current	0		(1,550)
Other Assets, Current	0		0
Assets, Current	(201)		(1,754)
Property, Plant and Equipment, Net	0		0
Goodwill	0		0
Intangible Assets, Net (Excluding Goodwill)	0		0
Other Assets, Noncurrent	0		0
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	(5,454,351)		(5,453,702)
Assets	(5,454,552)		(5,455,456)
LIABILITIES AND STOCKHOLDERS' EQUITY
Liabilities, Current	(201)		(204)
Long-term Debt, Excluding Current Maturities	0		0
Deferred income tax liabilities	0		(1,550)
Other noncurrent liabilities	0		0
Stockholders' equity	(5,454,351)		(5,453,702)
Total liabilities and stockholders' equity	(5,454,552)		(5,455,456)
Cash flows from financing activities:
Cash and cash equivalents at beginning of period			0
Cash and cash equivalents at end of period	0		0
Consolidating, Eliminating Adjustments [Member] | Guaranteed Senior Notes Payable [Member]
ASSETS
Cash and Cash Equivalents, at Carrying Value	0		0
Restricted Cash and Investments, Current	0		0
Accounts Receivable, Net, Current	(238,681)		(190,071)
Inventory, Net	0		0
Deferred Tax Assets, Net of Valuation Allowance, Current	(1,064)		(1,550)
Other Assets, Current	(10,825)		(10,825)
Assets, Current	(250,570)		(202,446)
Property, Plant and Equipment, Net	0		0
Goodwill	0		0
Intangible Assets, Net (Excluding Goodwill)	0		0
Other Assets, Noncurrent	(19,752)		(16,313)
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	(5,454,351)		(5,453,702)
Assets	(5,724,673)		(5,672,461)
LIABILITIES AND STOCKHOLDERS' EQUITY
Liabilities, Current	(249,506)		(200,896)
Long-term Debt, Excluding Current Maturities	(5,000)		(5,000)
Deferred income tax liabilities	(1,064)		(1,550)
Other noncurrent liabilities	(14,752)		(11,313)
Stockholders' equity	(5,454,351)		(5,453,702)
Total liabilities and stockholders' equity	(5,724,673)		(5,672,461)
Cash flows from financing activities:
Cash and cash equivalents at beginning of period			0
Cash and cash equivalents at end of period	$ 0		$ 0