ALLOWANCE FOR CREDIT LOSSES ON LOANS AND FINANCE LEASES - Activity in ACL on loans and finance leases (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Jan. 01, 2020
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	$ 155,139	$ 196,362
Provision (release) for credit losses	74,045	11,820
Charge-offs	(20,195)	(28,360)
Recoveries	2,620	3,910
Ending balance	292,774	183,732
ASC 326 \| Cumulative Effect Period Of Adoption Adjustment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Impact of adopting ASC 326 on Loans and Finance leases			$ 81,165
Residential Portfolio Segment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	44,806	50,794
Provision (release) for credit losses	16,218	6,639
Charge-offs	(4,435)	(6,173)
Recoveries	656	626
Ending balance	107,082	51,886
Residential Portfolio Segment [Member] \| ASC 326 \| Cumulative Effect Period Of Adoption Adjustment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Impact of adopting ASC 326 on Loans and Finance leases			49,837
Commercial Portfolio Segment [Member] \| Commercial And Industrial Sector [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	15,198	32,546
Provision (release) for credit losses	8,391	(5,009)
Charge-offs	(125)	(6,311)
Recoveries	115	1,095
Ending balance	38,310	22,321
Commercial Portfolio Segment [Member] \| Commercial And Industrial Sector [Member] \| ASC 326 \| Cumulative Effect Period Of Adoption Adjustment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Impact of adopting ASC 326 on Loans and Finance leases			14,731
Commercial Portfolio Segment [Member] \| Mortgage Receivable [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	39,194	55,581
Provision (release) for credit losses	14,167	121
Charge-offs	(128)	(2,400)
Recoveries	44	128
Ending balance	33,971	53,430
Commercial Portfolio Segment [Member] \| Mortgage Receivable [Member] \| ASC 326 \| Cumulative Effect Period Of Adoption Adjustment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Impact of adopting ASC 326 on Loans and Finance leases			(19,306)
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	2,370	3,592
Provision (release) for credit losses	2,062	(95)
Charge-offs	(3)	(207)
Recoveries	27	41
Ending balance	5,253	3,331
Commercial Portfolio Segment [Member] \| Construction Loans [Member] \| ASC 326 \| Cumulative Effect Period Of Adoption Adjustment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Impact of adopting ASC 326 on Loans and Finance leases			797
Consumer Portfolio Segment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	53,571	53,849
Provision (release) for credit losses	33,207	10,164
Charge-offs	(15,504)	(13,269)
Recoveries	1,778	2,020
Ending balance	$ 108,158	$ 52,764
Consumer Portfolio Segment [Member] \| ASC 326 \| Cumulative Effect Period Of Adoption Adjustment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Impact of adopting ASC 326 on Loans and Finance leases			$ 35,106

Impact of new accounting Principle in allowance for credit losses of financing receivalbe.

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- Definition

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 recovery of financing receivables doubtful of collection that were previously charged off.

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

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

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