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

No definition available.

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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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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of increase in allowance for credit loss on financing receivable from recovery.

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- Definition

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

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- Definition

Amount of allowance for credit loss at acquisition date of financing receivable purchased with credit deterioration.

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- Definition

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 - Activity in ACL on loans and finance leases (Detail) - USD ($) $ in Thousands			12 Months Ended
	Sep. 01, 2020	Jan. 01, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance		$ 155,139	$ 155,139	$ 196,362	$ 231,843
Allowance established for acquired PCD loans	$ 28,744	28,700
Provision (release) for credit losses			168,717	40,225	59,253
Charge-offs			(64,540)	(97,587)	(116,792)
Recoveries			16,662	16,139	22,058
Ending balance			385,887	155,139	196,362
ASC 326 [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Ending balance		236,304
ASC 326 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Impact of adopting ASC 326		81,165
Ending balance		81,165
Residential Portfolio Segment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance		44,806	44,806	50,794	58,975
Allowance established for acquired PCD loans	12,739
Provision (release) for credit losses			22,427	14,091	13,202
Charge-offs			(11,017)	(22,742)	(24,775)
Recoveries			1,519	2,663	3,392
Ending balance			120,311	44,806	50,794
Residential Portfolio Segment [Member] \| ASC 326 [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Ending balance		94,643
Residential Portfolio Segment [Member] \| ASC 326 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Impact of adopting ASC 326		49,837
Ending balance		49,837
Commercial Portfolio Segment [Member] \| Commercial And Industrial Sector [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance		15,198	15,198	32,546	48,871
Allowance established for acquired PCD loans	1,830
Provision (release) for credit losses			6,627	(13,696)	(8,440)
Charge-offs			(3,634)	(7,206)	(9,704)
Recoveries			3,192	3,554	1,819
Ending balance			37,944	15,198	32,546
Commercial Portfolio Segment [Member] \| Commercial And Industrial Sector [Member] \| ASC 326 [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Ending balance		29,929
Commercial Portfolio Segment [Member] \| Commercial And Industrial Sector [Member] \| ASC 326 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Impact of adopting ASC 326		14,731
Ending balance		14,731
Commercial Portfolio Segment [Member] \| Mortgage Receivable [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance		39,194	39,194	55,581	48,493
Allowance established for acquired PCD loans	9,723
Provision (release) for credit losses			81,125	(1,697)	23,074
Charge-offs			(3,330)	(15,088)	(23,911)
Recoveries			1,936	398	7,925
Ending balance			109,342	39,194	55,581
Commercial Portfolio Segment [Member] \| Mortgage Receivable [Member] \| ASC 326 [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Ending balance		19,888
Commercial Portfolio Segment [Member] \| Mortgage Receivable [Member] \| ASC 326 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Impact of adopting ASC 326		(19,306)
Ending balance		(19,306)
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance		2,370	2,370	3,592	4,522
Allowance established for acquired PCD loans	0
Provision (release) for credit losses			2,105	(1,496)	7,032
Charge-offs			(76)	(391)	(8,296)
Recoveries			184	665	334
Ending balance			5,380	2,370	3,592
Commercial Portfolio Segment [Member] \| Construction Loans [Member] \| ASC 326 [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Ending balance		3,167
Commercial Portfolio Segment [Member] \| Construction Loans [Member] \| ASC 326 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Impact of adopting ASC 326		797
Ending balance		797
Consumer Portfolio Segment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance		53,571	53,571	53,849	70,982
Allowance established for acquired PCD loans	$ 4,452
Provision (release) for credit losses			56,433	43,023	24,385
Charge-offs			(46,483)	(52,160)	(50,106)
Recoveries			9,831	8,859	8,588
Ending balance			$ 112,910	$ 53,571	$ 53,849
Consumer Portfolio Segment [Member] \| ASC 326 [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Ending balance		88,677
Consumer Portfolio Segment [Member] \| ASC 326 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Impact of adopting ASC 326		35,106
Ending balance		$ 35,106