This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses and taxes from ongoing operations before extraordinary items, and noncontrolling interest, plus income derived from interest on junior subordinated convertible debentures.

No definition available.

Earnings (Loss) Per Share Data (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Earnings (loss) per common share - Basic:
Income from continuing operations	$ (8,749)	$ 68,077	$ 61,246	$ 63,638	$ 58,627	$ (69,351)	$ 47,302	$ 48,314	$ 184,212	$ 84,892	$ 171,943
Loss from discontinued operations	2,700	(3,246)	(39,275)	136	(142,323)	3,042	4,917	6,040	(39,685)	(128,324)	22,931
Net income (loss)	(6,049)us-gaap_ProfitLoss	64,831us-gaap_ProfitLoss	21,971us-gaap_ProfitLoss	63,774us-gaap_ProfitLoss	(83,696)us-gaap_ProfitLoss	(66,309)us-gaap_ProfitLoss	52,219us-gaap_ProfitLoss	54,354us-gaap_ProfitLoss	144,527us-gaap_ProfitLoss	(43,432)us-gaap_ProfitLoss	194,874us-gaap_ProfitLoss
Common shares (in shares)	97,538,000	97,019,000	96,999,000	98,566,000	100,470,000	101,811,000	102,867,000	103,210,000	97,524,000	102,080,000	109,531,000
Basic earnings per share, continuing operations (per share)	$ (0.09)	$ 0.70	$ 0.63	$ 0.65	$ 0.58	$ (0.68)	$ 0.46	$ 0.47	$ 1.89	$ 0.83	$ 1.57
Basic earnings per share, discontinued operations (per share)	$ 0.03	$ (0.03)	$ (0.40)	$ 0.00	$ (1.42)	$ 0.03	$ 0.05	$ 0.06	$ (0.41)	$ (1.26)	$ 0.21
Earnings Per Share, Basic	$ (0.06)us-gaap_EarningsPerShareBasic	$ 0.67us-gaap_EarningsPerShareBasic	$ 0.23us-gaap_EarningsPerShareBasic	$ 0.65us-gaap_EarningsPerShareBasic	$ (0.83)us-gaap_EarningsPerShareBasic	$ (0.65)us-gaap_EarningsPerShareBasic	$ 0.51us-gaap_EarningsPerShareBasic	$ 0.53us-gaap_EarningsPerShareBasic	$ 1.48us-gaap_EarningsPerShareBasic	$ (0.43)us-gaap_EarningsPerShareBasic	$ 1.78us-gaap_EarningsPerShareBasic
Effect of Dilutive Securities [Abstract]
Stock options, warrants and awards									0	0	0
Interest Income Convertible Securities									264ocr_InterestIncomeConvertibleSecurities	281ocr_InterestIncomeConvertibleSecurities	284ocr_InterestIncomeConvertibleSecurities
convertible debentures, common shares (in shares)									8,129,000	6,736,000	2,891,000
Stock options, warrants and awards, common shares (in shares)									575,000	633,000	566,000
Diluted EPS [Abstract]
Loss from discontinued operations	2,700	(3,246)	(39,275)	136	(142,323)	3,042	4,917	6,040	(39,685)	(128,324)	22,931
Net income plus assumed conversions									144,791ocr_NetIncomePlusAssumedConversions	(43,151)ocr_NetIncomePlusAssumedConversions	195,158ocr_NetIncomePlusAssumedConversions
Diluted shares (in shares)	97,538,000	105,548,000	106,054,000	107,767,000	108,980,000	101,811,000	109,931,000	107,466,000	106,228,000	109,449,000	112,988,000
Diluted earnings per share, continuing operations plus assumed conversions (per share)	$ (0.09)	$ 0.65	$ 0.58	$ 0.59	$ 0.54	$ (0.68)	$ 0.43	$ 0.45	$ 1.74	$ 0.78	$ 1.52
Diluted earnings per share, discontinued operations (per share)	$ 0.03	$ (0.03)	$ (0.37)	$ 0.00	$ (1.31)	$ 0.03	$ 0.04	$ 0.06	$ (0.37)	$ (1.17)	$ 0.20
Earnings Per Share, Diluted	$ (0.06)us-gaap_EarningsPerShareDiluted	$ 0.61us-gaap_EarningsPerShareDiluted	$ 0.21us-gaap_EarningsPerShareDiluted	$ 0.59us-gaap_EarningsPerShareDiluted	$ (0.77)us-gaap_EarningsPerShareDiluted	$ (0.65)us-gaap_EarningsPerShareDiluted	$ 0.48us-gaap_EarningsPerShareDiluted	$ 0.51us-gaap_EarningsPerShareDiluted	$ 1.36us-gaap_EarningsPerShareDiluted	$ (0.39)us-gaap_EarningsPerShareDiluted	$ 1.73us-gaap_EarningsPerShareDiluted
Income from continuing operations plus assumed conversions									$ 184,476	$ 85,173	$ 172,227
Aggregate number of stock options, warrants and awards excluded from the computation of diluted EPS (in shares)										1,000,000	2,000,000
3.75% Convertible Senior Subordinated Notes, due 2025 [Member]
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Debt Instrument, Convertible, Conversion Price	$ 26.84								$ 26.84
4.00% Junior Subordinated Convertible Debentures, due 2033 [Member]
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Debt Instrument, Convertible, Conversion Price	$ 40.82								$ 40.82
3.25% Convertible Senior Debentures, Due 2035 [Member]
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Debt Instrument, Convertible, Conversion Price	$ 77.00								$ 77.00
3.25% Convertible Senior Subordinated Exchange Debentures, due 2035 [Member]
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Debt Instrument, Convertible, Conversion Price	$ 77.00								$ 77.00
3.5% Convertible senior subordinated debt [Domain]
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Debt Instrument, Convertible, Conversion Price	$ 70.00								$ 70.00