Fair Value Measurement - Reconciliation of Assets and Liabilities Measured at Fair Value Using Significant Unobservable Inputs (Level 3) on Recurring Basis (Detail) - Mortgage servicing rights - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	$ 5,168	$ 6,572	$ 6,200	$ 7,098
Transfers into (out of) Level 3	0	0	0	0
Change Included in Earnings	(1,236)	(552)	(2,494)	(1,197)
Issuances	318	209	544	328
Ending Balance	$ 4,250	$ 6,229	$ 4,250	$ 6,229