INVESTMENT SECURITIES - Reconciliation of the Par Value of Held-to-Maturity Acquired in the Santander Acquisition with the Purchase Price (Detail) $ in Thousands	Sep. 01, 2020 USD ($)
Debt and Equity Securities [Abstract]
Par value of acquired debt securities at acquisition	$ 67,082
Allowance for credit losses at acquisition	1,269
Non-credit discount at acquisition	10,281
Purchase price of debt securities at acquisition (initial fair value)	$ 55,532

Amount of allowance for credit loss at acquisition date of investment in debt security measured at amortized cost (held-to-maturity), purchased with credit deterioration.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 19
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919265-210447

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- Definition

Amount at par value of investment in debt security measured at amortized cost (held-to-maturity), purchased with credit deterioration.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 19
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919265-210447

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- Definition

Amount at purchase price of investment in debt security measured at amortized cost (held-to-maturity), purchased with credit deterioration.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 19
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919265-210447

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- Definition

Amount of discount (premium) attributable to other factors on investment in debt security measured at amortized cost (held-to-maturity), purchased with credit deterioration.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 19
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919265-210447

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- References

No definition available.

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