Income Taxes - Effective Income Tax Expense (Benefit) Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Statutory amount (computed at 35%)	$ (714)	$ (3,703)	$ 3,519
State income tax, net of federal benefit	94	(709)	(312)
Permanent differences	99	43	122
Permanent differences, incentive stock options	224	298	157
True up to prior year taxes	109	0	(311)
Valuation allowance, current	1,769
Valuation allowance	3,321	1,552	0
Total	$ 1,581	$ (2,519)	$ 3,175
Consolidated effective tax rate	(77.50%)	23.80%	31.60%