Income Taxes-Effective Income Tax Rate Reconciliation (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2018	Mar. 31, 2017
Effective Income Tax Rate Reconciliation, Amount
Statutory Federal income tax expense (benefit), Amount									$ 1,638	$ (929)
State and local income tax, net of Federal tax benefit, Amount									92	119
Impact of income tax rate changes, Amount									3,283	0
Credit and NOL adjustments, Amount									(2,148)	0
Change in Valuation Allowance, Amount									(3,061)	961
Other, Amount									163	(32)
Income tax (benefit) expense	$ (124)	$ 31	$ 30	$ 30	$ 82	$ 0	$ 0	$ 37	$ (33)	$ 119
Effective Income Tax Rate Reconciliation, Percent
Statutory Federal income tax expense (benefit), Percent									30.80%	34.00%
State and local income tax, net of Federal tax benefit, Percent									1.70%	(4.40%)
Impact of income tax rate changes, Percent									61.70%	0.00%
Credit and NOL adjustments, Percent									(40.40%)	0.00%
Change in Valuation Allowance, Percent									(57.50%)	(35.20%)
Other, Percent									3.10%	1.20%
Income tax expense (benefit), Percent									(0.60%)	(4.40%)