CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Cash flows from operating activities:
Net (loss) income	$ (30,483)	$ 6,423
Adjustments to reconcile net (loss) income to net cash from operating activities:
Share-based compensation	6,513	9,353
Depreciation	3,340	2,519
Amortization of intangible assets	500	498
Amortization of discount on notes receivable	0	(100)
Amortization of deferred financing costs and discount	116	85
Non-cash lease expenses	492
Loss on fixed asset disposal	313	0
Impairment of intangible assets	1,258	0
Change in deferred income taxes	0	(4,279)
Increase (decrease) in cash resulting from changes in:
Inventory	1,034	(1,912)
Prepaid expenses	4,125	(181)
Income tax receivable	(80)	655
Other current assets	(1,527)	(1,013)
Accounts payable	(4,072)	4,518
Accrued compensation	(3,814)	(533)
Accrued expenses	10,975	13,343
Income taxes	0	1,715
Other liabilities	(1,820)	(226)
Net cash flows (used in) provided by operating activities	(13,130)	30,865
Cash flows from investing activities:
Purchases of equipment	(899)	(5,541)
Principal payments on note receivable	389	0
Patent application costs	(253)	(40)
Net cash flows used in investing activities	(763)	(5,581)
Cash flows from financing activities:
Proceeds from term loan	72,750	0
Deferred financing costs	(6,045)	0
Share repurchase for tax withholdings on vesting of restricted stock	(1,109)	(4,404)
Proceeds from exercise of stock options	108	3,554
Share repurchase under repurchase plan	0	(7,572)
Payments under capital lease obligations		(3)
Net cash flows used in financing activities	65,704	(8,425)
Net change in cash	51,811	16,859
Cash and cash equivalents, beginning of period	45,118	27,476
Cash and cash equivalents, end of period	$ 96,929	$ 44,335