Fair Value Measurement - Assets and Liabilities Measured at Fair Value on Nonrecurring Basis (Detail) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Foreclosed assets (Residential real estate)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	$ 313
Individually evaluated loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	684		$ 3,683
Fair Value Nonrecurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	997	$ 4,771	3,683
Total Losses	(909)	(2,741)	(1,105)
Fair Value Nonrecurring Basis | Individually evaluated loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	684	4,557	3,683
Total Losses	(615)	(2,710)	(1,105)
Fair Value Nonrecurring Basis | Foreclosed Assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value		214
Total Losses		(31)
Fair Value Nonrecurring Basis | Foreclosed Assets | Foreclosed assets (Residential real estate)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	313		0
Total Losses	(294)		0
Fair Value Nonrecurring Basis | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	0	0	0
Fair Value Nonrecurring Basis | Level 1 | Individually evaluated loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	0	0	0
Fair Value Nonrecurring Basis | Level 1 | Foreclosed Assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value		0
Fair Value Nonrecurring Basis | Level 1 | Foreclosed Assets | Foreclosed assets (Residential real estate)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	0		0
Fair Value Nonrecurring Basis | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	0	0	0
Fair Value Nonrecurring Basis | Level 2 | Individually evaluated loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	0	0	0
Fair Value Nonrecurring Basis | Level 2 | Foreclosed Assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value		0
Fair Value Nonrecurring Basis | Level 2 | Foreclosed Assets | Foreclosed assets (Residential real estate)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	0		0
Fair Value Nonrecurring Basis | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	997	4,771	3,683
Fair Value Nonrecurring Basis | Level 3 | Individually evaluated loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	684	4,557	3,683
Fair Value Nonrecurring Basis | Level 3 | Foreclosed Assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value		$ 214
Fair Value Nonrecurring Basis | Level 3 | Foreclosed Assets | Foreclosed assets (Residential real estate)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	$ 313		$ 0