FAIR VALUE OF FINANCIAL INSTRUMENTS - Assets and Liabilities Measured at Fair Value on a Recurring and Nonrecurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Financial Assets
Derivative assets	$ 130,294	$ 154,485
Financial Liabilities
Derivative liabilities	115,568	137,335
Recurring \| Cash flow hedges
Financial Assets
Derivative assets	14,726	17,150
Recurring \| Freestanding derivatives, net
Financial Assets
Derivative assets	115,568	137,335
Financial Liabilities
Derivative liabilities	115,568	137,335
Recurring \| Level 2 Inputs \| Cash flow hedges
Financial Assets
Derivative assets	14,726	17,150
Recurring \| Level 2 Inputs \| Freestanding derivatives, net
Financial Assets
Derivative assets	115,568	137,335
Financial Liabilities
Derivative liabilities	115,568	137,335
Nonrecurring \| Level 3 Inputs
Certain individually evaluated loans
Individually evaluated loans	1,945	1,179
Carrying Amount
Certain individually evaluated loans
Individually evaluated loans	10,651,565	10,482,145
Carrying Amount \| Nonrecurring
Certain individually evaluated loans
Individually evaluated loans	1,945	1,179
Agency Notes \| Recurring
Financial Assets
Securities available-for-sale:	9,291
Agency Notes \| Recurring \| Level 2 Inputs
Financial Assets
Securities available-for-sale:	9,291
Treasury Securities \| Recurring
Financial Assets
Securities available-for-sale:	230,431	227,256
Treasury Securities \| Recurring \| Level 2 Inputs
Financial Assets
Securities available-for-sale:	230,431	227,256
Corporate Securities \| Recurring
Financial Assets
Securities available-for-sale:	143,882	166,773
Corporate Securities \| Recurring \| Level 2 Inputs
Financial Assets
Securities available-for-sale:	143,882	166,773
Pass-through mortgage-backed securities ("MBS") issued by government sponsored entities ("GSEs") \| Recurring
Financial Assets
Mortgage-backed securities	235,074	241,240
Pass-through mortgage-backed securities ("MBS") issued by government sponsored entities ("GSEs") \| Recurring \| Level 2 Inputs
Financial Assets
Mortgage-backed securities	235,074	241,240
Agency collateralized mortgage obligations ("CMOs") \| Recurring
Financial Assets
Securities available-for-sale:	278,394	281,339
Agency collateralized mortgage obligations ("CMOs") \| Recurring \| Level 2 Inputs
Financial Assets
Securities available-for-sale:	278,394	281,339
State and municipal obligations. \| Recurring
Financial Assets
Securities available-for-sale:	29,740	33,979
State and municipal obligations. \| Recurring \| Level 2 Inputs
Financial Assets
Securities available-for-sale:	$ 29,740	$ 33,979

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

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-Publisher FASB
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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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Fair value of securitized, pay-through debt securities collateralized by real estate mortgage loans classified as available-for-sale.

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