Revenue from Contracts with Customers - Contract Assets, Contract Liabilities and Receivables from Contracts with Customers (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017	Sep. 30, 2017
Revenue from Contract with Customer [Abstract]
Contract assets	$ 0	$ 0	$ 0
Contract liabilities	1,429	1,706	1,799
Mortgage broker fees receivable	9	69	69
Administrative services receivable	2,425	0	0
Wealth management receivable	7,779	8,102	7,443
Card related fees receivable	0	202	89
Total receivables from contracts with customer	$ 10,213	$ 8,373	$ 7,601