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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 | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Financial Assets |  |
Derivative assets | $ 154,485 | $ 45,086
Financial Liabilities |  |
Derivative liabilities | 137,335 | 40,728
Certain individually evaluated loans |  |
Individually evaluated loans | 1,200 |
Recurring | Cash flow hedges |  |
Financial Assets |  |
Derivative assets | 17,150 | 4,358
Recurring | Freestanding derivatives, net |  |
Financial Assets |  |
Derivative assets | 137,335 | 40,728
Financial Liabilities |  |
Derivative liabilities | 137,335 | 40,728
Recurring | Level 2 Inputs | Cash flow hedges |  |
Financial Assets |  |
Derivative assets | 17,150 | 4,358
Recurring | Level 2 Inputs | Freestanding derivatives, net |  |
Financial Assets |  |
Derivative assets | 137,335 | 40,728
Financial Liabilities |  |
Derivative liabilities | 137,335 | 40,728
Nonrecurring | Level 3 Inputs |  |
Certain individually evaluated loans |  |
Individually evaluated loans | 1,179 | 1,900
Carrying Amount |  |
Certain individually evaluated loans |  |
Individually evaluated loans | 10,482,145 | 9,158,908
Carrying Amount | Nonrecurring |  |
Certain individually evaluated loans |  |
Individually evaluated loans | 1,179 | 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: | 227,256 | 244,769
Treasury Securities | Recurring | Level 2 Inputs |  |
Financial Assets |  |
Securities available-for-sale: | 227,256 | 244,769
Corporate Securities | Recurring |  |
Financial Assets |  |
Securities available-for-sale: | 166,773 | 152,030
Corporate Securities | Recurring | Level 2 Inputs |  |
Financial Assets |  |
Securities available-for-sale: | 166,773 | 152,030
Pass-through mortgage-backed securities ("MBS") issued by government sponsored entities ("GSEs") | Recurring |  |
Financial Assets |  |
Marketable equity securities (Registered Mutual Funds) |  | 526,454
Mortgage-backed securities | 241,240 |
Pass-through mortgage-backed securities ("MBS") issued by government sponsored entities ("GSEs") | Recurring | Level 2 Inputs |  |
Financial Assets |  |
Marketable equity securities (Registered Mutual Funds) |  | 526,454
Mortgage-backed securities | 241,240 |
Agency collateralized mortgage obligations ("CMOs") | Recurring |  |
Financial Assets |  |
Securities available-for-sale: | 281,339 | 521,258
Agency collateralized mortgage obligations ("CMOs") | Recurring | Level 2 Inputs |  |
Financial Assets |  |
Securities available-for-sale: | 281,339 | 521,258
State and municipal obligations. | Recurring |  |
Financial Assets |  |
Securities available-for-sale: | 33,979 | 38,946
State and municipal obligations. | Recurring | Level 2 Inputs |  |
Financial Assets |  |
Securities available-for-sale: | $ 33,979 | $ 38,946

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