ALLOWANCE FOR CREDIT LOSSES ON LOANS AND FINANCE LEASES - Carrying Amount of Portfolios (Detail) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2022	Dec. 31, 2021	Mar. 31, 2022	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020
Financing Receivable Allowance For Credit Losses [Line Items]
Amortized cost of loans	$ 11,206,874	$ 11,060,658
Allowance for credit losses	252,152	269,030	$ 245,447	$ 324,958	$ 358,936	$ 385,887
Residenital Mortgage Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Amortized cost of loans	2,851,685	2,978,895
Allowance for credit losses	$ 65,231	$ 74,837	68,820	112,882	114,044	120,311
Residenital 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	2.29%	2.51%
Commercial Portfolio Segment [Member] | Commercial And Industrial Sector [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Amortized cost of loans	$ 2,862,917	$ 2,887,251
Allowance for credit losses	$ 36,203	$ 34,284	36,784	37,470	32,087	37,944
Commercial Portfolio Segment [Member] | Commercial And Industrial Sector [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	1.26%	1.19%
Commercial Portfolio Segment [Member] | Mortgage Receivable [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Amortized cost of loans	$ 2,270,113	$ 2,167,469
Allowance for credit losses	$ 32,619	$ 52,771	30,138	72,452	99,782	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	1.44%	2.43%
Commercial Portfolio Segment [Member] | Construction Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Amortized cost of loans	$ 115,310	$ 138,999
Allowance for credit losses	$ 2,020	$ 4,048	1,842	4,757	4,915	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	1.75%	2.91%
Consumer Portfolio Segment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Amortized cost of loans	$ 3,106,849	$ 2,888,044
Allowance for credit losses	$ 116,079	$ 103,090	$ 107,863	$ 97,397	$ 108,108	$ 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	3.74%	3.57%
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	2.25%	2.43%