Business Segment Information (Details 3) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013	Dec. 31, 2012
Operating results by business segment
Restricted cash	$ 165,166	$ 236,696
Net accounts receivable	302,682	238,185
Investments	201,424	208,313
Pharmaceutical inventory	40,899	49,609
Goodwill	566,106	488,206	426,939
Other intangible assets, net	140,313	69,694
Public Sector
Operating results by business segment
Goodwill	20,879	20,882
Specialty Solutions
Operating results by business segment
Goodwill	104,549	104,549
Pharmacy Management
Operating results by business segment
Goodwill	311,636	242,290
Operating segments | Commercial
Operating results by business segment
Restricted cash	18,579	25,107
Net accounts receivable	56,898	50,407
Investments	18,089	16,491
Goodwill	129,042	120,485
Other intangible assets, net	2,402	3,513
Operating segments | Public Sector
Operating results by business segment
Restricted cash	144,882	196,651
Net accounts receivable	60,377	62,977
Investments	159,959	92,966
Goodwill	20,879	20,882
Other intangible assets, net	6,651	4,590
Operating segments | Specialty Solutions
Operating results by business segment
Net accounts receivable	14,912	7,368
Goodwill	104,549	104,549
Other intangible assets, net	2,675	3,686
Operating segments | Pharmacy Management
Operating results by business segment
Net accounts receivable	165,936	115,527
Pharmaceutical inventory	40,899	49,609
Goodwill	311,636	242,290
Other intangible assets, net	128,585	57,905
Corporate and Elimination
Operating results by business segment
Restricted cash	1,705	14,938
Net accounts receivable	4,559	1,906
Investments	$ 23,376	$ 98,856