Premises and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Abstract]
Leasehold improvements	$ 31,451	$ 29,207
Furniture and equipment	29,667	26,994
Less accumulated depreciation and amortization	(40,127)	(35,540)
Total premises and equipment, net	$ 20,991	$ 20,661