CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Cash flows from operating activities:
Net loss	$ (54,242)	$ (36,560)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Depreciation and amortization	59,485	27,994
Provision for bad debt expense	463	590
Amortization of premium/discount on purchased securities	67	113
Non-cash equity-based compensation expense	5,533	5,778
Amortization of debt discount and debt issuance costs	3,880	3,209
Gains on marketable securities, net	0	(143)
Change in fair value of contingent consideration	626	1,043
Deferred income taxes	(6,643)	(21,192)
Changes in operating assets and liabilities:
Accounts receivable, net	3,093	6,553
Inventories	3,534	(403)
Prepaid and other current assets	(3,720)	1,523
Accounts payable and accrued expenses	30,374	(4,622)
Deferred revenues	3,027	2,067
Other assets and liabilities	215	(486)
Net cash provided by (used in) operating activities	45,692	(14,536)
Cash flows from investing activities:
Proceeds from sales or maturities of marketable securities	18,225	128,512
Purchase of marketable securities	(21,102)	(129,241)
Capital expenditures	(923)	(658)
Net cash used in investing activities	(3,800)	(1,387)
Cash flows from financing activities:
Long-term debt principal payments	0	(4,375)
Payments of contingent consideration	(44)	(83)
Proceeds from the exercise of common stock options	123	152
Payments of employee tax withholding related to equity-based compensation	(2,348)	(1,322)
Net cash used in financing activities	(2,269)	(5,628)
Net increase (decrease) in cash, cash equivalents, and restricted cash	39,623	(21,551)
Cash, cash equivalents, and restricted cash at beginning of the period	192,770	276,898
Cash, cash equivalents, and restricted cash at end of the period	232,393	255,347
Supplemental data for cash flow information:
Cash paid for taxes	136	208
Cash paid for interest	$ 18,971	$ 26,195