Fair Value Measurements (Impaired Loans Remeasured and Reported at Fair Value of Underlying Collateral) (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Carrying value before allocations	$ 1,333	$ 1,559	$ 2,354
Specific valuation allowance allocations		(450)	(383)
Reversal of specific valuation allowance allocations	214
Fair value	1,547	1,109	1,971
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Carrying value before allocations	16,074	34,302	65,176
Specific valuation allowance allocations	(5,178)	(11,151)	(18,019)
Fair value	$ 10,896	$ 23,151	$ 47,157