Balance Sheet Account Detail - Schedule of Amounts Presented in Accounts Payable and Other Accrued Liabilities (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
	Mar. 31, 2015	Dec. 31, 2014
Rebates and Chargebacks [Member]
Accounts Payable and Other Liabilities [Roll Forward]
Beginning balance	$ 45,822	$ 33,967
Add: provisions	24,926	76,636
(Less): credits or actual allowances	(23,218)	(64,781)
Ending balance	47,530	45,822
Data and Distribution, GPO Fees, and Inventory Management Fees [Member]
Accounts Payable and Other Liabilities [Roll Forward]
Beginning balance	8,284	5,373
Add: provisions	6,002	21,330
(Less): credits or actual allowances	(6,279)	(18,419)
Ending balance	8,007	8,284
Returns [Member]
Accounts Payable and Other Liabilities [Roll Forward]
Beginning balance	1,135	2,900
Add: provisions	583	(78)
(Less): credits or actual allowances	(337)	(1,687)
Ending balance	$ 1,381	$ 1,135