Condensed Consolidating Financial Statements Cash Flows (Details) (USD $)
In Thousands, unless otherwise specified
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Cash flows from operating activities:      
Net cash provided (used) by operating activities $ 590,181 $ 475,421 $ 249,733
Cash flows from investing activities:      
Acquisitions, net of cash acquired (2,026) (388,866) (1,565,705)
Purchases of property and equipment (78,078) (128,842) (40,236)
Proceeds from restricted cash 20,006 20,004 0
Net cash used in investing activities (60,098) (497,704) (1,605,941)
Cash flows from financing activities:      
Proceeds from issuance of debt 492,500 450,000 1,475,448
Repayment of long-term debt (337,500) (362,500) (616,993)
Proceeds from public offering, net of issuance costs 0 0 519,075
Payment of financing costs (1,963) (2,347) (18,806)
Proceeds from exercise of options and warrants   3,479 7,763
Proceeds from exercise of options 5,639 2,992 7,763
Tax benefit on option exercises 3,492 9,732 19,397
Proceeds from warrants exercised 3,452 487 0
Payments of contingent consideration (18,338) (23,203)  
Distribution to non-controlling interest (52,309) (36,314) 0
Net transactions with parent and affiliates 0 0 0
Proceeds from restricted stock 0 0 0
Other (383) 0 (268)
Net cash provided by financing activities 94,590 38,847 1,385,616
Effect of foreign exchange on cash balances 38 (99) (14)
Increase in cash and cash equivalents 624,711 16,465 29,394
Cash and cash equivalents, beginning of period 387,241 370,776 341,382
Cash and cash equivalents, end of period 1,011,952 387,241 370,776
Reportable Legal Entities | Catamaran Corporation      
Cash flows from operating activities:      
Net cash provided (used) by operating activities 341,698 186,985 (27,257)
Cash flows from investing activities:      
Acquisitions, net of cash acquired 0 0 3,644,364
Purchases of property and equipment (71) (11) (66)
Proceeds from restricted cash 0 0  
Net cash used in investing activities (71) (11) 3,644,298
Cash flows from financing activities:      
Proceeds from issuance of debt 492,500 450,000 1,475,448
Repayment of long-term debt (337,500) (362,500) (616,993)
Proceeds from public offering, net of issuance costs     519,075
Payment of financing costs (1,963) (2,347) (18,806)
Proceeds from exercise of options and warrants   4,729 11,016
Proceeds from exercise of options 8,011    
Tax benefit on option exercises 0 0 0
Proceeds from warrants exercised 3,452    
Payments of contingent consideration 0 0  
Distribution to non-controlling interest 0 0  
Net transactions with parent and affiliates (208,486) (322,377) (5,093,214)
Proceeds from restricted stock 20,700 27,107 17,903
Other 0 0 (268)
Net cash provided by financing activities (23,286) (205,388) (3,705,839)
Effect of foreign exchange on cash balances 38 (99) (14)
Increase in cash and cash equivalents 318,379 (18,513) (88,812)
Cash and cash equivalents, beginning of period 15,090 33,603 122,415
Cash and cash equivalents, end of period 333,469 15,090 33,603
Reportable Legal Entities | Guarantors      
Cash flows from operating activities:      
Net cash provided (used) by operating activities 612,430 616,168 430,091
Cash flows from investing activities:      
Acquisitions, net of cash acquired (2,026) (388,866) (5,210,069)
Purchases of property and equipment (41,664) (117,799) (30,549)
Proceeds from restricted cash 20,006 20,004  
Net cash used in investing activities (23,684) (486,661) (5,240,618)
Cash flows from financing activities:      
Proceeds from issuance of debt 0 0 0
Repayment of long-term debt 0 0 0
Proceeds from public offering, net of issuance costs     0
Payment of financing costs 0 0 0
Proceeds from exercise of options and warrants   (1,248) (3,253)
Proceeds from exercise of options (2,355)    
Tax benefit on option exercises 3,455 9,704 19,206
Proceeds from warrants exercised 0    
Payments of contingent consideration (18,338) (18,338)  
Distribution to non-controlling interest 0 0  
Net transactions with parent and affiliates (264,620) (49,103) 4,913,963
Proceeds from restricted stock (20,249) (26,645) (17,651)
Other (383) 0 0
Net cash provided by financing activities (302,490) (85,630) 4,912,265
Effect of foreign exchange on cash balances 0 0 0
Increase in cash and cash equivalents 286,256 43,877 101,738
Cash and cash equivalents, beginning of period 362,647 318,770 217,032
Cash and cash equivalents, end of period 648,903 362,647 318,770
Reportable Legal Entities | Non-Guarantors      
Cash flows from operating activities:      
Net cash provided (used) by operating activities (6,952) (30,476) (18,449)
Cash flows from investing activities:      
Acquisitions, net of cash acquired 0 0 0
Purchases of property and equipment (36,343) (11,032) (9,621)
Proceeds from restricted cash 0 0  
Net cash used in investing activities (36,343) (11,032) (9,621)
Cash flows from financing activities:      
Proceeds from issuance of debt 0 0 0
Repayment of long-term debt 0 0 0
Proceeds from public offering, net of issuance costs     0
Payment of financing costs 0 0 0
Proceeds from exercise of options and warrants   (2) 0
Proceeds from exercise of options (17)    
Tax benefit on option exercises 37 28 191
Proceeds from warrants exercised 0    
Payments of contingent consideration 0 (4,865)  
Distribution to non-controlling interest 0 0  
Net transactions with parent and affiliates 63,802 37,910 44,599
Proceeds from restricted stock (451) (462) (252)
Other 0 0 0
Net cash provided by financing activities 63,371 32,609 44,538
Effect of foreign exchange on cash balances 0 0 0
Increase in cash and cash equivalents 20,076 (8,899) 16,468
Cash and cash equivalents, beginning of period 9,504 18,403 1,935
Cash and cash equivalents, end of period 29,580 9,504 18,403
Consolidations      
Cash flows from operating activities:      
Net cash provided (used) by operating activities (356,995) (297,256) (134,652)
Cash flows from investing activities:      
Acquisitions, net of cash acquired 0 0 0
Purchases of property and equipment 0 0   
Proceeds from restricted cash 0 0  
Net cash used in investing activities 0 0 0
Cash flows from financing activities:      
Proceeds from issuance of debt 0 0 0
Repayment of long-term debt 0 0 0
Proceeds from public offering, net of issuance costs     0
Payment of financing costs 0 0 0
Proceeds from exercise of options and warrants   0 0
Proceeds from exercise of options 0    
Tax benefit on option exercises 0 0 0
Proceeds from warrants exercised 0    
Payments of contingent consideration 0 0  
Distribution to non-controlling interest (52,309) (36,314)  
Net transactions with parent and affiliates 409,304 333,570 134,652
Proceeds from restricted stock 0 0 0
Other 0 0 0
Net cash provided by financing activities 356,995 297,256 134,652
Effect of foreign exchange on cash balances 0 0 0
Increase in cash and cash equivalents 0 0 0
Cash and cash equivalents, beginning of period 0 0 0
Cash and cash equivalents, end of period $ 0 $ 0 $ 0