Allowance for Loan Losses - Summary of Changes in Loan Allowance (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Schedule of changes in allowance for loan losses
Balance at the beginning of the year				$ 35,042				$ 32,086	$ 35,042	$ 32,086	$ 31,083
Charge-offs									(4,989)	(3,605)	(4,838)
Recoveries of loans previously charged-off									1,807	1,432	1,621
Provision for loan losses	$ 1,558	$ 466	$ 1,367	$ 920	$ 1,162	$ 1,065	$ 1,750	$ 1,152	4,311	5,129	4,220
Balance at the end of the year	$ 36,171				$ 35,042				$ 36,171	$ 35,042	$ 32,086