Summary of Significant Accounting Policies - Recently Issued Accounting Pronouncements (Details) - USD ($) $ in Thousands	Jan. 01, 2019	Dec. 31, 2018	Jan. 01, 2018	Dec. 31, 2017
Assets
Accounts receivable, net		$ 102,922	$ 67,206	$ 65,586
Deferred income taxes (asset)		29,683	20,109	20,843
Liabilities
Deferred licensing revenue				287
Deferred licensing revenue, net of current portion				1,149
Equity
Accumulated deficit/(Retained earnings)		$ (86,492)	24,501	$ 26,823
Effect of Change Higher (Lower)
Assets
Accounts receivable, net			1,620
Deferred income taxes (asset)			(734)
Liabilities
Deferred licensing revenue			(287)
Deferred licensing revenue, net of current portion			(1,149)
Equity
Accumulated deficit/(Retained earnings)			$ (2,322)
Restatement Adjustment | Accounting Standards Update 2016-02
Equity
Lease assets	$ 4,000
Lease liabilities	$ 4,000