FAIR VALUE OF FINANCIAL INSTRUMENTS - Assets and Liabilities Measured at Fair Value on a Recurring and Nonrecurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Financial Assets
Derivative assets	$ 162,679	$ 45,086
Financial Liabilities
Derivative liabilities	144,343	40,728
Recurring \| Cash flow hedges
Financial Assets
Derivative assets	18,336	4,358
Recurring \| Freestanding derivatives, net
Financial Assets
Derivative assets	144,343	40,728
Financial Liabilities
Derivative liabilities	144,343	40,728
Recurring \| Level 2 Inputs \| Cash flow hedges
Financial Assets
Derivative assets	18,336	4,358
Recurring \| Level 2 Inputs \| Freestanding derivatives, net
Financial Assets
Derivative assets	144,343	40,728
Financial Liabilities
Derivative liabilities	144,343	40,728
Nonrecurring \| Level 3 Inputs
Certain individually evaluated loans
Individually evaluated loans	1,453	1,900
Carrying Amount
Certain individually evaluated loans
Individually evaluated loans	10,033,553	9,158,908
Carrying Amount \| Nonrecurring
Certain individually evaluated loans
Individually evaluated loans	1,453	1,900
Agency Notes \| Recurring
Financial Assets
Securities available-for-sale:		80,254
Agency Notes \| Recurring \| Level 2 Inputs
Financial Assets
Securities available-for-sale:		80,254
Treasury Securities \| Recurring
Financial Assets
Securities available-for-sale:	225,925	244,769
Treasury Securities \| Recurring \| Level 2 Inputs
Financial Assets
Securities available-for-sale:	225,925	244,769
Corporate Securities \| Recurring
Financial Assets
Securities available-for-sale:	157,032	152,030
Corporate Securities \| Recurring \| Level 2 Inputs
Financial Assets
Securities available-for-sale:	157,032	152,030
Pass-through mortgage-backed securities ("MBS") issued by government sponsored entities ("GSEs") \| Recurring
Financial Assets
Mortgage-backed securities	252,655	526,454
Pass-through mortgage-backed securities ("MBS") issued by government sponsored entities ("GSEs") \| Recurring \| Level 2 Inputs
Financial Assets
Mortgage-backed securities	252,655	526,454
Agency collateralized mortgage obligations ("CMOs") \| Recurring
Financial Assets
Securities available-for-sale:	293,717	521,258
Agency collateralized mortgage obligations ("CMOs") \| Recurring \| Level 2 Inputs
Financial Assets
Securities available-for-sale:	293,717	521,258
State and municipal obligations. \| Recurring
Financial Assets
Securities available-for-sale:	33,598	38,946
State and municipal obligations. \| Recurring \| Level 2 Inputs
Financial Assets
Securities available-for-sale:	$ 33,598	$ 38,946

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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.

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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.

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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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