Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Jan. 08, 2016
Deferred tax assets:
Accounts receivable and financing receivables	$ 1,395	$ 1,392
Accrued vacation	519	1,022
Stock-based compensation	1,416	1,678
Deferred revenue	132	894
Accrued severance	207	75
Accrued liabilities and other	884	1,025
Fixed assets	172	0
Credits	0	349
Net operating loss	13,261	26,689
Deferred tax assets	17,986	33,124
Less: Valuation allowance	1,605	1,624	$ 1,600
Total deferred tax assets	16,381	31,500
Deferred tax liabilities:
Intangible assets	21,048	34,696
Fixed assets	0	50
Total deferred tax liabilities	21,048	34,746
Total net deferred tax liability	$ (4,667)	$ (3,246)