Segment Information (Details) (USD $)
In Thousands, unless otherwise specified
3 Months Ended9 Months Ended3 Months Ended9 Months Ended12 Months Ended3 Months Ended9 Months Ended3 Months Ended9 Months Ended
Sep. 30, 2011
Sep. 30, 2010
Sep. 30, 2011
Sep. 30, 2010
Dec. 31, 2010
Sep. 30, 2011
Customer Concentration Risk [Member]
Sales [Member]
customers
Sep. 30, 2010
Customer Concentration Risk [Member]
Sales [Member]
customers
Sep. 30, 2011
Customer Concentration Risk [Member]
Sales [Member]
customers
Sep. 30, 2010
Customer Concentration Risk [Member]
Sales [Member]
customers
Sep. 30, 2011
Customer Concentration Risk [Member]
Accounts Receivable [Member]
customers
Dec. 31, 2010
Customer Concentration Risk [Member]
Accounts Receivable [Member]
customers
Sep. 30, 2011
P B M [Member]
Sep. 30, 2010
P B M [Member]
Sep. 30, 2011
P B M [Member]
Sep. 30, 2010
P B M [Member]
Sep. 30, 2011
H C I T [Member]
Sep. 30, 2010
H C I T [Member]
Sep. 30, 2011
H C I T [Member]
Sep. 30, 2010
H C I T [Member]
Segment Reporting Information [Line Items]                   
Revenues$ 1,287,290$ 489,922$ 3,596,981$ 1,421,516       $ 1,256,369$ 463,042$ 3,511,148$ 1,341,839$ 30,921$ 26,880$ 85,833$ 79,677
Cost of revenue1,204,948437,0583,376,8591,264,684       1,188,197423,7733,330,8861,225,62016,75113,28545,97339,064
Gross profit82,34252,864220,122156,832       68,17239,269180,262116,21914,17013,59539,86040,613
Total assets$ 997,098$ 754,560$ 997,098$ 754,560$ 816,790      $ 690,445$ 491,117$ 690,445$ 491,117$ 306,653$ 263,443$ 306,653$ 263,443
Concentration Risk Percentage During Period     39.00% 40.00%           
Concentration Risk, Percentage         17.00%         
Number of Customers Accounting for Greater Than Ten Percent (in number of customers)     101010