CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Operating Activities
Net (loss) income	$ (14,301)	$ 33,824
Adjustments for non-cash items:
Depreciation and amortization	25,990	26,918
Accretion of debt discount and debt issuance costs	6,164	5,418
Provision for inventory obsolescence	359	218
Gain on disposal of property and equipment	0	(134)
Stock-based compensation	2,702	2,234
Change in fair value of contingent consideration	28	(201)
Other	1,297	34
Changes in assets and liabilities:
Accounts receivable	(6,278)	10,055
Inventories	(40)	7,457
Prepaid and other assets	30,592	(34,497)
Accounts payable and other accrued liabilities	(12,361)	(33,515)
Accrued rebates, returns and discounts	(4,105)	(42,730)
Interest payable	(2,852)	(2,055)
Income taxes payable	0	(1)
Net cash provided by (used in) operating activities	27,195	(26,975)
Investing Activities
Purchases of property and equipment	(13)	(1)
Proceeds from disposal of property and equipment	0	145
Proceeds from sale of other assets	0	80
Maturities of marketable securities	0	1,200
Net cash provided by (used in) investing activities	(13)	1,424
Financing Activities
Payment of contingent consideration liability	0	(162)
Repayment of Senior Notes	(25,000)	0
Fees for modification of Senior Notes	(3,249)	0
Proceeds from issuance of common stock	25	636
Shares withheld for payment of employee's withholding tax liability	(216)	(114)
Net cash provided by (used in) financing activities	(28,440)	360
Net (decrease) in cash and cash equivalents	(1,258)	(25,191)
Cash and cash equivalents at beginning of year	110,949	126,884
Cash and cash equivalents at end of year	109,691	101,693
Supplemental Disclosure of Cash Flow Information
Net cash paid for income taxes	0	1
Cash paid for interest	13,213	14,653
Capital expenditures incurred but not yet paid	$ 130	$ 119