Deposits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Interest expense on deposits [Abstract]
Transaction deposits	$ 13,906	$ 8,821	$ 9,757
Savings	386	383	401
Time Deposit, Interest Expense [Abstract]
Certificates of deposits under $100,000	8,776	11,894	14,278
Certificates of deposits $100,000 and over	10,123	10,643	11,878
Other time deposits	7,303	12,429	14,369
Total time	26,202	34,966	40,525
Total	40,494	44,170	$ 50,683
Time Deposit Information [Abstract]
Time deposits in denomination of $250,000 or more	866,000	905,000
Time Deposit Maturities [Abstract]
2017	1,300,000
2018	340,000
2019	71,000
2020	94,000
2021	114,000
Thereafter	342,000
Fixed rate, brokered certificates of deposits	$ 417,000	$ 358,000
Weighted-average interest rate paid on fixed rate, brokered certificates of deposits (in hundredths)	1.33%	1.48%
Other Deposits Information [Abstract]
Overdrawn customer transaction deposits reclassified as loan balances	$ 9,700	$ 5,300