Fair Value Measurement of Assets and Liabilities - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Fair Value Disclosures [Abstract]
Impaired collateral dependent loans, charge-offs	$ 158	$ 0	$ 1,100	$ 0
Collateral dependent impaired loans, recorded investment	81,900		81,900
Specific valuation allowance allocations	34,300		34,300
Reported net carrying amount of impaired loans	47,600		$ 47,600
Valuation of loan servicing rights, prepayment rate			12.00%
Valuation of loan servicing rights, discount rate			9.60%
Loan servicing rights	715		$ 715
Net impairment (net recovery)	64	(48)	(19)	(365)
Foreclosed assets measured at fair value upon initial recognition			3,700
Foreclosed asset charge-offs	668	267	2,100	1,500
Loss due to re-measurement of foreclosed assets	$ 379	$ 245	$ 539	$ 390