Amount, after recoveries, of loans and leases that have been written-off.

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Amount of increase (decrease) in allowance for credit loss on financing receivable.

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Amount of writeoff of financing receivable, charged against allowance for credit loss.

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Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

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Amount of expense (reversal of expense) for expected credit loss for off-balance sheet credit exposure. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

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Amount of expense related to estimated loss from loan and lease transactions.

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ALLOWANCE FOR CREDIT LOSSES ON LOANS AND FINANCE LOSSES - Additional Information (Detail) - USD ($) $ in Thousands		3 Months Ended			6 Months Ended
	Jan. 01, 2020	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses on loans and finance leases		$ 319,297	$ 292,774	$ 172,011	$ 319,297	$ 172,011	$ 155,139	$ 183,732	$ 196,362
Increase (decrease) in ACL					164,200
Provision (release) for credit losses		36,408	74,000	12,534	110,453	24,354
Net charge-offs		9,900	17,600	24,200	27,500
Charge-offs		12,049		27,913	32,244	56,273
ACL for unfunded loan commitments and standby letters of credit		7,084	5,741	0	7,084	0	0	0	412
Provison (release) for credit losses on unfunded loan commitments and standby letters of credit		1,343		0	3,162	(412)
Build Reserve		26,500
Commercial Portfolio Segment [Member] \| Mortgage Receivable [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses on loans and finance leases		49,435	$ 33,971	46,373	49,435	46,373	$ 39,194	$ 53,430	$ 55,581
Provision (release) for credit losses		15,439		4,541	29,606	4,662
Charge-offs		$ 18		$ 11,688	146	14,088
Commercial Portfolio Segment [Member] \| Mortgage Receivable [Member] \| Florida region [Member] \| Nonperforming Financing Receivable [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Charge-offs						$ 11,400
COVID-19
Financing Receivable Allowance For Credit Losses [Line Items]
Increase (decrease) in ACL					88,900
Build Reserve					$ 83,000
ASC 326
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses on loans and finance leases	$ 236,304
ACL for unfunded loan commitments and standby letters of credit	3,922
ASC 326 \| Commercial Portfolio Segment [Member] \| Mortgage Receivable [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses on loans and finance leases	19,888
ASC 326 \| Cumulative Effect Period Of Adoption Adjustment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses on loans and finance leases	81,165
Increase (decrease) in ACL	(434)
ACL for unfunded loan commitments and standby letters of credit	3,922
ASC 326 \| Cumulative Effect Period Of Adoption Adjustment [Member] \| Commercial Portfolio Segment [Member] \| Mortgage Receivable [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses on loans and finance leases	$ (19,306)