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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 20
-Name Accounting Standards Codification
-Section 40
-Paragraph 7
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-URI https://asc.fasb.org/1943274/2147481628/310-20-40-7

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Section 50
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Name Accounting Standards Codification
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Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 35
-Publisher FASB
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LOANS HELD FOR INVESTMENT - Additional Information II (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest Income Recognized on Nonaccrual Loans	$ 0.5	$ 0.4	$ 1.4	$ 1.4
Residential Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans in process of foreclosure amount	32.1		$ 32.1
Loans foreclosure delinquency threshold			120 days
Residential Portfolio Segment [Member] \| Loans Insured or Guaranteed by US Government Authorities [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans in process of foreclosure amount	12.3		$ 12.3
Residential Portfolio Segment [Member] \| Financial Asset Acquired with Credit Deterioration [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans in process of foreclosure amount	4.5		4.5
Nonperforming Financial Instruments [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable accrued interest writeoff	$ 0.8	$ 0.9	$ 2.3	$ 2.0