LOAN PORTFOLIO - Corporation's TDR Activity (Detail) - Entity Loan Modification Program [Member] - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Financing Receivable Modifications [Line Items]
Beginning Balance of TDRs	$ 589,795	$ 572,376	$ 582,647	$ 587,219
New TDRs	6,961	13,228	32,420	56,647
Increases to existing TDRs (disbursements)	347	75	1,522	6,846
Charge-offs post modification	(2,092)	(8,616)	(4,913)	(17,787)
Foreclosures	(3,278)	(3,759)	(6,921)	(10,802)
TDRs transferred to loans held for sale	0	0	0	(30,000)
Paid-off and partial payments	(9,344)	(16,108)	(22,366)	(34,927)
Ending balance of TDRs	$ 582,389	$ 557,196	$ 582,389	$ 557,196

Disbursements during the period on existing commitments of TDRs loans.

No definition available.

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- Definition

Recorded investment in loans that were modified under troubled debt restructurings during the period.

+ References

No definition available.

+ Details

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- Definition

Repayments related to Trouble Debt Restructuring Loans.

+ References

No definition available.

+ Details

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- Definition

Amount of real estate investments acquired through foreclosure during the period related to troubled debt restructurings.

+ References

No definition available.

+ Details

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- Definition

Troubled debt restrcuturings transferred to loans held for sale during the period.

+ References

No definition available.

+ Details

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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.

+ Details

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- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18845-111554

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- Definition

Reflects the amount of the write-down related to a troubled debt restructuring.

+ References

+ Details

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