Fair Value Measurements and Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Impaired Financing Receivable, with Related Allowance, Recorded Investment	$ 3,793
Impaired Financing Receivable, Related Allowance	147	$ 39
Taxi Medallion loans charged off during period	17,000
Impaired Loans [Member]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	3,800	1,100
Impaired Financing Receivable, Related Allowance	100	$ 39
Collateral dependent Taxi Medallion loans carrying value	$ 29,400