General (Details 3) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Significant customers
Major customer defined (as a percent)			10.00%	10.00%
Revenues generated	$ 698,338	$ 741,658	$ 1,391,093	$ 1,469,711
Minimum number of contracts per customer			1
Commercial
Significant customers
Revenues generated	139,686	160,982	289,721	322,684
Commercial | Customer A
Significant customers
Revenues generated			91,606	126,875
Commercial | Customer B
Significant customers
Revenues generated			33,402	36,833
Commercial | Customer C
Significant customers
Revenues generated			54,796	23,317
Public Sector
Significant customers
Revenues generated	362,284	368,011	712,800	717,479
Public Sector | Customer D
Significant customers
Revenues generated			81,060	72,631
Radiology Benefits Management
Significant customers
Revenues generated	90,608	105,263	179,820	214,720
Radiology Benefits Management | Wellpoint, Inc.
Significant customers
Revenues generated				79,280
Radiology Benefits Management | Customer E
Significant customers
Revenues generated			67,392	53,396
Radiology Benefits Management | Customer F
Significant customers
Revenues generated			30,934	34,384
Radiology Benefits Management | Customer G
Significant customers
Revenues generated			26,720	25,933
Specialty Pharmaceutical Management
Significant customers
Revenues generated	69,366	67,993	139,596	136,131
Specialty Pharmaceutical Management | Customer E
Significant customers
Revenues generated			13,314	17,121
Specialty Pharmaceutical Management | Customer H
Significant customers
Revenues generated			42,989	43,310
Specialty Pharmaceutical Management | Customer I
Significant customers
Revenues generated			27,963	30,396
Medicaid Administration
Significant customers
Revenues generated	56,637	39,409	109,930	78,697
Medicaid Administration | Customer J
Significant customers
Revenues generated			13,805	15,804
Medicaid Administration | Customer K
Significant customers
Revenues generated			40,774
Medicaid Administration | Customer L
Significant customers
Revenues generated			12,466	11,530
Medicaid Administration | Customer M
Significant customers
Revenues generated			8,680	10,888
Medicaid Administration | Customer N
Significant customers
Revenues generated				9,457
Medicaid Administration | Customer O
Significant customers
Revenues generated			11,411	7,939
Maricopa County Regional Behavioral Health Authority
Significant customers
Major customer defined (as a percent)			10.00%	10.00%
Revenues generated			383,600	400,900
Number of members receiving behavioral healthcare management and other related services			719,000
Termination notice (in days)			10
Customer D
Significant customers
Number of contract extensions available under option			3
Contract extension period available under option (in years)			1
Wellpoint, Inc.
Significant customers
Revenues generated				$ 87,100