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FAIR VALUE OF FINANCIAL INSTRUMENTS - Assets and Liabilities Measured at Fair Value on a Recurring and Nonrecurring Basis (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Financial Assets
Derivative assets	$ 45,086	$ 18,932
Financial Liabilities
Derivative liabilities	40,728	37,374
Impaired Loans [Abstract]
Individually evaluated CRE loans with an allowance for credit losses, Outstanding balance	1,900	12,502
With related allowance recorded	1,900	12,502
Valuation allowance		6,474
Provision for credit losses	6,212	26,165	$ 17,340
Recurring \| Cash flow hedges
Financial Assets
Derivative assets	4,358
Financial Liabilities
Derivative liabilities		18,442
Recurring \| Freestanding derivatives, net
Financial Assets
Derivative assets	40,728	30,596
Financial Liabilities
Derivative liabilities	40,728	30,596
Recurring \| Level 2 Inputs [Member] \| Cash flow hedges
Financial Assets
Derivative assets	4,358
Financial Liabilities
Derivative liabilities		18,442
Recurring \| Level 2 Inputs [Member] \| Freestanding derivatives, net
Financial Assets
Derivative assets	40,728	30,596
Financial Liabilities
Derivative liabilities	40,728	30,596
Nonrecurring [Member]
Impaired Loans [Abstract]
Individually evaluated CRE loans with an allowance for credit losses, Outstanding balance	2,500
With related allowance recorded	2,500
Valuation allowance	600
Provision for credit losses	600
Nonrecurring [Member] \| Level 3 Inputs [Member]
Impaired Loans [Abstract]
Individually evaluated loans	1,900
Carrying Amount \| Nonrecurring [Member]
Impaired Loans [Abstract]
Individually evaluated loans	1,900
Agency Notes \| Recurring
Financial Assets
Securities available-for-sale:	80,254	47,421
Agency Notes \| Recurring \| Level 2 Inputs [Member]
Financial Assets
Securities available-for-sale:	80,254	47,421
Treasury Securities \| Recurring
Financial Assets
Securities available-for-sale:	244,769
Treasury Securities \| Recurring \| Level 2 Inputs [Member]
Financial Assets
Securities available-for-sale:	244,769
Corporate Securities \| Recurring
Financial Assets
Securities available-for-sale:	152,030	64,461
Corporate Securities \| Recurring \| Level 2 Inputs [Member]
Financial Assets
Securities available-for-sale:	152,030	64,461
Pass-through mortgage-backed securities ("MBS") issued by government sponsored entities ("GSEs") \| Recurring
Financial Assets
Securities available-for-sale:		143,483
Mortgage-backed securities	526,454
Pass-through mortgage-backed securities ("MBS") issued by government sponsored entities ("GSEs") \| Recurring \| Level 2 Inputs [Member]
Financial Assets
Securities available-for-sale:		143,483
Mortgage-backed securities	526,454
Agency collateralized mortgage obligations ("CMOs") \| Recurring
Financial Assets
Securities available-for-sale:	521,258	283,496
Agency collateralized mortgage obligations ("CMOs") \| Recurring \| Level 2 Inputs [Member]
Financial Assets
Securities available-for-sale:	521,258	283,496
State and municipal obligations. \| Recurring
Financial Assets
Securities available-for-sale:	38,946
State and municipal obligations. \| Recurring \| Level 2 Inputs [Member]
Financial Assets
Securities available-for-sale:	$ 38,946
Domestic Equity Mutual Funds \| Recurring
Financial Assets
Marketable equity securities (Registered Mutual Funds)		1,769
Domestic Equity Mutual Funds \| Recurring \| Level 1 Inputs [Member]
Financial Assets
Marketable equity securities (Registered Mutual Funds)		1,769
International Equity Mutual Funds \| Recurring
Financial Assets
Marketable equity securities (Registered Mutual Funds)		468
International Equity Mutual Funds \| Recurring \| Level 1 Inputs [Member]
Financial Assets
Marketable equity securities (Registered Mutual Funds)		468
Fixed Income Mutual Funds \| Recurring
Financial Assets
Marketable equity securities (Registered Mutual Funds)		3,733
Fixed Income Mutual Funds \| Recurring \| Level 1 Inputs [Member]
Financial Assets
Marketable equity securities (Registered Mutual Funds)		$ 3,733