FAIR VALUE MEASURES - Difference Between Fair Value and Principal Balance of Loans Held for Sale Measured at Fair Value (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Mortgage loans held for sale
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Aggregate fair value of loans held for sale	$ 1,430,695	$ 998,050
Aggregate unpaid principal balance of loans held for sale	1,389,380	947,460
Past-due loans of 90 days or more	152	0
Nonaccrual loans	152	0
Unpaid principal balance of nonaccrual loans	149	0
SBA loans held for sale
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Aggregate fair value of loans held for sale	5,110	3,757
Aggregate unpaid principal balance of loans held for sale	4,446	3,393
Past-due loans of 90 days or more	0	0
Nonaccrual loans	$ 0	$ 0

Aggregate fair value of loans held for sale.

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- Definition

Aggregate Unpaid Principal Balance Of Items For Which Fair Value Option Was Elected

+ References

No definition available.

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- Definition

Fair Value, Option, Loans Held as Assets, Unpaid Principal Balance of Nonaccrual Status, Aggregated Difference

+ References

No definition available.

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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

For loans held as assets for which the fair value option has been elected, this item represents the difference between the aggregate fair value and the aggregate unpaid principal balance of those loans that are 90 days or more past due.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 28
-Subparagraph (e)(3)
-URI http://asc.fasb.org/extlink&oid=123596393&loc=d3e14064-108612

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