Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Cash flows from operating activities
Net income	$ 76,902	$ 7,092
Adjustments to reconcile net income to net cash provided by operating activities:
Loss on extinguishment of debt	382	2,400
Change in fair value of derivative liability	(349)	(66)
Depreciation and amortization	1,728	651
Unrealized loss on marketable securities		47
Amortization of deferred financing costs and debt discount	512	646
Non-cash interest expense on liability related to sale of future royalties	3,564	2,530
Non-cash royalty revenue	(3,464)	(2,007)
Share-based compensation expense	4,454	3,011
Deferred income tax benefit	(42,377)
Changes in operating assets and liabilities:
Accounts receivable	(10,312)	(6,334)
Inventories	(4,866)	(1,301)
Prepaid expenses and other assets	1,060	(2,793)
Accounts payable	(1,629)	949
Accrued sales deduction	12,900	10,359
Accrued expenses	3,314	(459)
Deferred licensing revenue	195	(107)
Other non-current liabilities	(140)	(21)
Net cash provided by operating activities	41,874	14,597
Cash flows from investing activities
Purchases of marketable securities	(31,194)	(51,942)
Sales and maturities of marketable securities	22,398	33,671
Purchases of property and equipment	(1,302)	(1,240)
Deferred legal fees	(12,224)	(6,908)
Net cash used in investing activities	(22,322)	(26,419)
Cash flows from financing activities
Proceeds from issuance of common stock	1,255	1,067
Net cash provided by financing activities	1,255	1,067
Net change in cash and cash equivalents	20,807	(10,755)
Cash and cash equivalents at beginning of period	33,498	36,396
Cash and cash equivalents at end of period	54,305	25,641
Supplemental cash flow information:
Cash paid for interest	247	504
Non-cash financial activity:
Conversion of convertible notes and interest make-whole	2,138	26,019
Exercise of warrants		652
Deferred legal fees included in accounts payable and accrued expenses	$ 7,920	$ 6,866