Deposits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Interest expense on deposits [Abstract]
Transaction deposits	$ 65,859	$ 28,627	$ 13,906
Savings	439	359	386
Time Deposit, Interest Expense [Abstract]
Certificates of deposits under $100,000	5,751	7,702	8,776
Certificates of deposits $100,000 and over	19,739	12,393	10,123
Other time deposits	3,729	4,722	7,303
Total time	29,219	24,817	26,202
Total	95,517	53,803	$ 40,494
Time Deposit Information [Abstract]
Time deposits in denomination of $250,000 or more	756,000	797,000
Time Deposit Maturities [Abstract]
2019	1,300,000
2020	262,000
2021	98,000
2022	115,000
2023	130,000
Thereafter	211,000
Other Deposits Information [Abstract]
Overdrawn customer transaction deposits reclassified as loan balances	$ 27,000	$ 5,900