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ALLOWANCE FOR CREDIT LOSSES FOR LOANS AND FINANCE LEASES - Carrying Amount of Portfolios (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Financing Receivable Allowance For Credit Losses [Line Items]
Amortized cost of loans	$ 12,185,483	$ 11,552,825
Allowance for credit losses	261,843	260,464	$ 269,030	$ 385,887
Residential Mortgage Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Amortized cost of loans	2,821,726	2,847,290
Allowance for credit losses	$ 57,397	$ 62,760	74,837	120,311
Residential Mortgage Loans [Member] \| Allowance for loan and lease losses, numerator [Member] \| Amortized cost, denominator [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses to amortized cost	2.03%	2.20%
Commercial Portfolio Segment [Member] \| C & I Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Amortized cost of loans	$ 3,174,232	$ 2,886,263
Allowance for credit losses	$ 33,190	$ 32,906	34,284	37,944
Commercial Portfolio Segment [Member] \| C & I Loans [Member] \| Allowance for loan and lease losses, numerator [Member] \| Amortized cost, denominator [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses to amortized cost	1.05%	1.14%
Commercial Portfolio Segment [Member] \| Mortgage Receivable [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Amortized cost of loans	$ 2,317,083	$ 2,358,851
Allowance for credit losses	$ 32,631	$ 35,064	52,771	109,342
Commercial Portfolio Segment [Member] \| Mortgage Receivable [Member] \| Allowance for loan and lease losses, numerator [Member] \| Amortized cost, denominator [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses to amortized cost	1.41%	1.49%
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Amortized cost of loans	$ 214,777	$ 132,953
Allowance for credit losses	$ 5,605	$ 2,308	4,048	5,380
Commercial Portfolio Segment [Member] \| Construction Loans [Member] \| Allowance for loan and lease losses, numerator [Member] \| Amortized cost, denominator [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses to amortized cost	2.61%	1.74%
Consumer Portfolio Segment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Amortized cost of loans	$ 3,657,665	$ 3,327,468
Allowance for credit losses	$ 133,020	$ 127,426	$ 103,090	$ 112,910
Consumer Portfolio Segment [Member] \| Allowance for loan and lease losses, numerator [Member] \| Amortized cost, denominator [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses to amortized cost	3.64%	3.83%
Loan Total [Member] \| Allowance for loan and lease losses, numerator [Member] \| Amortized cost, denominator [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses to amortized cost	2.15%	2.25%