Revenue Recognition - Summary of Company's Revenue Streams (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
NONINTEREST INCOME
Loan servicing income									$ 2,028	$ 1,840	$ 1,445
Earnings on bank-owned life insurance									7,160	3,486	3,427
Net gain from sales of loans									8,609	6,642	10,759
Net gain from sales of investment securities									13,882	8,571	1,399
Other income									12,201	4,486	3,641
Total noninterest income	$ 23,194	$ 26,758	$ 6,898	$ 14,475	$ 9,801	$ 11,430	$ 6,324	$ 7,681	71,325	35,236	31,027
Service charges on deposit accounts
NONINTEREST INCOME
Noninterest income									6,712	5,769	5,128
Other service fee income
NONINTEREST INCOME
Noninterest income									1,554	1,438	902
Debit card interchange income
NONINTEREST INCOME
Noninterest income									2,526	3,004	4,326
Trust custodial account fees
NONINTEREST INCOME
Noninterest income									16,653	0	0
Within Scope
NONINTEREST INCOME
Other income									3,090	1,015	1,242
Total noninterest income									30,535	11,226	11,598
Within Scope | Service charges on deposit accounts
NONINTEREST INCOME
Noninterest income									6,712	5,769	5,128
Within Scope | Other service fee income
NONINTEREST INCOME
Noninterest income									1,554	1,438	902
Within Scope | Debit card interchange income
NONINTEREST INCOME
Noninterest income									2,526	3,004	4,326
Within Scope | Trust custodial account fees
NONINTEREST INCOME
Noninterest income									16,653	0	0
Out-of-Scope
NONINTEREST INCOME
Loan servicing income									2,028	1,840	1,445
Earnings on bank-owned life insurance									7,160	3,486	3,427
Net gain from sales of loans									8,609	6,642	10,759
Net gain from sales of investment securities									13,882	8,571	1,399
Other income									9,111	3,471	2,399
Total noninterest income									$ 40,790	$ 24,010	$ 19,429