Income Taxes - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Statutory federal corporate tax rate		34.00%	34.00%	34.00%
Deferred tax not recongized	$ 14,900	$ 14,900	$ 14,900
Deferred Tax Assets, Net	12,563	12,563	22,411
Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount	$ 2,500	$ 2,487	$ 0	$ 0