Balance Sheet Account Detail - Schedule of Amounts Presented in Accounts Payable and Other Accrued Obligations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Rebates and Chargebacks [Member]
Accounts Payable and Other Accrued Liabilities [Roll Forward]
Beginning balance	$ 10,358	$ 9,817
Add: provisions	65,751	106,647
(Less): credits or actual allowances	(65,008)	(106,106)
Ending balance	11,101	10,358
Data and Distribution, GPO Fees, and Inventory Management Fees [Member]
Accounts Payable and Other Accrued Liabilities [Roll Forward]
Beginning balance	5,727	5,146
Add: provisions	13,962	20,104
(Less): credits or actual allowances	(15,757)	(19,523)
Ending balance	3,932	5,727
Returns [Member]
Accounts Payable and Other Accrued Liabilities [Roll Forward]
Beginning balance	4,045	2,309
Add: provisions	1,700	2,807
(Less): credits or actual allowances	(574)	(1,071)
Ending balance	$ 5,171	$ 4,045