Business Segment Information - Changes Related to Allocation of Corporate Operational Support Functions (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Summary of changes by business segment
Segment profit (loss) before Corporate allocations	$ 59,932	$ 64,947
Segment profit (loss)	59,932	64,947
Operating segments \| Healthcare
Summary of changes by business segment
Segment profit (loss) before Corporate allocations	53,527	67,948
Allocated Corporate costs	(17,641)	(17,947)
Allocated Corporate stock compensation expense	1,324	2,199
Segment profit (loss)	37,210	52,200
Operating segments \| Pharmacy Management
Summary of changes by business segment
Segment profit (loss) before Corporate allocations	32,707	24,505
Allocated Corporate costs	(4,541)	(4,685)
Allocated Corporate stock compensation expense	331	549
Segment profit (loss)	28,497	20,369
Corporate and Elimination
Summary of changes by business segment
Segment profit (loss) before Corporate allocations	(26,302)	(27,506)
Allocated Corporate costs	22,182	22,632
Allocated Corporate stock compensation expense	(1,655)	(2,748)
Segment profit (loss)	$ (5,775)	$ (7,622)

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Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1,2)
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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