Business Segment Information - Operating Results by Segment (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Operating results by business segment
Managed care and other revenue		$ 699,861	$ 776,240	$ 1,376,322	$ 1,524,890
PBM and dispensing revenue		464,484	381,367	905,045	613,685
Cost of care		(472,529)	(568,288)	(930,160)	(1,090,616)
Cost of goods sold		(436,930)	(361,409)	(852,389)	(579,616)
Direct service costs and other	[1],[2],[3]	(214,077)	(191,455)	(406,533)	(395,905)
Stock compensation expense		9,510	13,795	18,397	27,696
Changes in fair value of contingent consideration		463	2,567	197	17,536
Impairment of intnagilbe assets		4,800		4,800
Less: non-controlling interest segment profit (loss)		(1,312)	(350)	(1,147)	(444)
Segment profit (loss)		56,894	53,167	116,826	118,114
Operating segments | Healthcare
Operating results by business segment
Managed care and other revenue		637,970	722,471	1,256,898	1,422,064
Cost of care		(472,529)	(568,288)	(930,160)	(1,090,621)
Direct service costs and other		(139,965)	(124,779)	(265,582)	(253,247)
Stock compensation expense		2,451	1,784	4,470	4,972
Changes in fair value of contingent consideration		390	71	70	171
Impairment of intnagilbe assets		4,800		4,800
Less: non-controlling interest segment profit (loss)		(1,305)	(273)	(1,136)	(393)
Segment profit (loss)		34,422	31,532	71,632	83,732
Operating segments | Pharmacy Management
Operating results by business segment
Managed care and other revenue		61,975	53,782	119,552	102,850
PBM and dispensing revenue		495,399	408,924	965,633	667,717
Cost of care					5
Cost of goods sold		(466,637)	(387,828)	(910,586)	(631,366)
Direct service costs and other		(64,086)	(61,038)	(124,927)	(129,271)
Stock compensation expense		5,548	10,339	10,970	19,744
Changes in fair value of contingent consideration		73	2,496	127	17,365
Segment profit (loss)		32,272	26,675	60,769	47,044
Corporate and Elimination
Operating results by business segment
Managed care and other revenue		(84)	(13)	(128)	(24)
PBM and dispensing revenue		(30,915)	(27,557)	(60,588)	(54,032)
Cost of goods sold		29,707	26,419	58,197	51,750
Direct service costs and other		(10,026)	(5,638)	(16,024)	(13,387)
Stock compensation expense		1,511	1,672	2,957	2,980
Less: non-controlling interest segment profit (loss)		(7)	(77)	(11)	(51)
Segment profit (loss)		$ (9,800)	$ (5,040)	$ (15,575)	$ (12,662)

[1] Includes changes in fair value of contingent consideration of $2,567 and $463 for the three months ended June 30, 2015 and 2016, respectively, and $17,536 and $197 for the six months ended June 30, 2015 and 2016, respectively.Includes impairment of intangible assets of $4,800 for the three and six months ended June 30, 2016.

[2] Includes impairment of intangible assets of $4,800 for the three and six months ended June 30, 2016.

[3] Includes stock compensation expense of $13,795 and $9,510 for the three months ended June 30, 2015 and 2016, respectively,