Revenue Recognition - Summary of Company's Revenue Streams (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018
Interest income:
Loans	$ 121,476	$ 126,341	$ 84,173
Investment securities and other interest-earning assets	9,767	9,680	6,654
Total interest income	131,243	136,021	90,827
Noninterest income:
Loan servicing fees	398	408	345
Earnings on bank-owned life insurance	910	929	611
Net gain from sales of loans	1,729	1,929	2,958
Net gain from sales of investment securities	427	0	6
Other income	1,460	944	1,414
Total noninterest income	7,681	6,970	7,666
Service charges on deposit accounts
Noninterest income:
Noninterest income	1,330	1,351	1,150
Other service fee income
Noninterest income:
Noninterest income	356	270	146
Debit card interchange fee income
Noninterest income:
Noninterest income	1,071	1,139	1,036
Within Scope
Noninterest income:
Other income	192	1,158	237
Total noninterest income	2,949	3,918	2,569
Total revenues	2,949	3,918	2,569
Within Scope | Service charges on deposit accounts
Noninterest income:
Noninterest income	1,330	1,351	1,150
Within Scope | Other service fee income
Noninterest income:
Noninterest income	356	270	146
Within Scope | Debit card interchange fee income
Noninterest income:
Noninterest income	1,071	1,139	1,036
Out of Scope
Interest income:
Loans	121,476	126,341	84,173
Investment securities and other interest-earning assets	9,767	9,680	6,654
Total interest income	131,243	136,021	90,827
Noninterest income:
Loan servicing fees	398	408	345
Earnings on bank-owned life insurance	910	929	611
Net gain from sales of loans	1,729	1,929	2,958
Net gain from sales of investment securities	427	0	6
Other income	1,268	(214)	1,177
Total noninterest income	4,732	3,052	5,097
Total revenues	$ 135,975	$ 139,073	$ 95,924