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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 |

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