Income Taxes - Deferred Taxes (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Deferred tax assets:
Net operating loss carryforwards	$ 11,566	$ 44,587
Stock based compensation	5,012	1,767
Fair value royalty agreements	3,386	2,435
Fair value contingent consideration	2,152	1,348
Other	583	1,037
Total deferred tax assets	22,699	51,174
Valuation allowances	(7,599)	(45,516)
Net deferred tax assets	15,100	5,658
Deferred tax liabilities:
Amortization	(4,349)	(5,649)
Accounts receivable	(3,319)	0
Total deferred tax liabilities	(7,668)	(5,649)
Net deferred tax assets	$ 7,432	$ 9