Income Taxes - Reconciliation of Change in Federal and State Gross Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance at beginning of year	$ 1,102	$ 284	$ 1,902
Increase	0	818	55
Decrease	(449)	0	(1,673)
Current period tax positions	151	0	0
Reductions for statute of limitations expirations	0	0	0
Balance at End of Year	804	1,102	284
Amount That Would Affect the Effective Tax Rate if Recognized	$ 610	$ 542	$ 184