Selected Quarterly Financial Data (Unaudited) - Tabular Disclosure (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Net revenue:
Net revenue	$ 1,184,960	$ 1,170,117	$ 1,100,075	$ 1,122,379	$ 1,133,775	$ 1,158,543	$ 1,154,289	$ 1,119,006	$ 4,577,531	$ 4,565,613	$ 4,957,522
Costs and expenses:
Cost of care	362,478	364,438	321,831	349,108	367,819	397,697	408,911	369,097	1,397,855	1,543,524	1,554,691
Cost of goods sold	559,140	560,269	528,067	533,241	507,917	523,973	501,081	526,314	2,180,717	2,059,285	2,452,703
Direct service costs and other operating expenses	259,401	216,770	199,756	204,241	207,616	195,844	195,907	202,300	880,168	801,667	773,915
Depreciation and amortization	26,411	24,730	23,888	23,358	27,869	28,890	28,191	25,417	98,387	110,367	112,284
Interest expense	6,626	7,286	7,995	8,958	8,826	8,935	9,070	9,037	30,865	35,868	35,180
Interest and other income	(1,935)	(349)	(551)	(1,219)	(1,578)	(1,699)	(1,821)	(1,759)	(4,054)	(6,857)	(4,884)
Special charges	9,170	16,599	8,309						34,078
Total costs and expenses	1,221,291	1,189,743	1,089,295	1,117,687	1,118,469	1,153,640	1,141,339	1,130,406	4,618,016	4,543,854	4,923,889
Income (loss) from continuing operations before income taxes	(36,331)	(19,626)	10,780	4,692	15,306	4,903	12,950	(11,400)	(40,485)	21,759	33,633
Provision (benefit) for income taxes	(11,635)	(2,330)	(36,328)	5,762	5,854	782	5,735	(3,209)	(44,531)	9,162	11,457
Net income (loss) from continuing operations	(24,696)	(17,296)	47,108	(1,070)	9,452	4,121	7,215	(8,191)	4,046	12,597	22,176
Income from discontinued operations, net of tax	293,629	28,943	36,397	19,320	11,132	17,153	6,398	8,622	378,289	43,305	2,005
Net income	$ 268,933	$ 11,647	$ 83,505	$ 18,250	$ 20,584	$ 21,274	$ 13,613	$ 431	$ 382,335	$ 55,902	$ 24,181
Weighted average number of common shares outstanding-basic (in shares)	25,781	25,448	25,054	24,728	24,491	24,426	24,101	23,946	25,255	24,243	24,349
Weighted average number of common shares outstanding-diluted	25,781	25,448	25,278	24,869	24,905	24,708	24,416	24,213	25,532	24,563	25,035
Net income per common share - basic:
Continuing operations (in dollars per share)	$ (0.96)	$ (0.68)	$ 1.88	$ (0.04)	$ 0.39	$ 0.17	$ 0.30	$ (0.34)	$ 0.16	$ 0.52	$ 0.91
Discontinued operations (in dollars per share)	11.39	1.14	1.45	0.78	0.45	0.70	0.26	0.36	14.98	1.79	0.08
Consolidated operations (in dollars per share)	10.43	0.46	3.33	0.74	0.84	0.87	0.56	0.02	15.14	2.31	0.99
Net income per common share - diluted:
Continuing operations (in dollars per share)	(0.96)	(0.68)	1.86	(0.04)	0.38	0.17	0.30	(0.34)	0.16	0.51	0.89
Discontinued operations (in dollars per share)	11.39	1.14	1.44	0.78	0.45	0.69	0.26	0.36	14.82	1.76	0.08
Consolidated operations (in dollars per share)	$ 10.43	$ 0.46	$ 3.30	$ 0.74	$ 0.83	$ 0.86	$ 0.56	$ 0.02	$ 14.98	$ 2.27	$ 0.97
Managed care and other
Net revenue:
Net revenue	$ 579,454	$ 568,688	$ 548,711	$ 553,168	$ 580,544	$ 591,229	$ 608,614	$ 566,548	$ 2,250,021	$ 2,346,935	$ 2,350,576
PBM
Net revenue:
Net revenue	$ 605,506	$ 601,429	$ 551,364	$ 569,211	$ 553,231	$ 567,314	$ 545,675	$ 552,458	$ 2,327,510	$ 2,218,678	$ 2,606,946