Fair Value Measurement - Quantitative Information about Level 3 Fair Value Measurements (Detail) - Assets Measured at Fair Value on a Nonrecurring Basis [Member] - (Level 3) [Member] - Mortgage Servicing Rights [Member] $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value	$ 2,999	$ 3,018
Valuation Technique	Discounted Cash Flow	Discounted Cash Flow
Constant Prepayment Rate [Member] | Minimum [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Unobservable Input	4.4	4.6
Constant Prepayment Rate [Member] | Maximum [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Unobservable Input	11.1	11
Constant Prepayment Rate [Member] | Weighted Average [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Unobservable Input	6	6
Discount Rate [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Unobservable Input	12	12
Discount Rate [Member] | Weighted Average [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Unobservable Input	12	12