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SECURITIES - Narrative (Details) - USD ($) | 9 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Sep. 30, 2022 | Sep. 30, 2021 | Dec. 31, 2021 | Jan. 01, 2021
Securities available-for-sale: |  |  |  |
Securities available-for-sale transferred to held-to-maturity | $ 372,154,000 |  |  |
Transfers Of Securities Held-to-maturity To Securities Available-for-sale | 0 |  |  |
Transfers To Or From Securities Held-to-maturity |  | 0 |  |
Securities held-to-maturity | $ 511,054,000 |  | $ 177,354,000 | $ 0
Number of holdings of securities of any one issuer in an amount greater than 10% of stockholders equity | 0 |  | 0 |
Threshold for disclosure percentage | 10.00% |  | 10.00% |
Available for sale debt securities, unrealized loss position due to credit | $ 0 |  |  |
Allowance for credit losses on available for sale debt securities | 0 |  |  |
Accrued interest receivable on securities | 4,600,000 |  | $ 4,400,000 |
Unrealized loss on transfer of securities to held to maturity | (27,800,000) |  |  |
Gain (loss) on transfer of securities to held-to-maturity | 0 |  |  |
Unrealized losses are related to credit losses | 0 |  |  |
Securities pledged |  |  |  |
Securities available-for-sale: |  |  |  |
Carrying amount of securities pledged | $ 651,100,000 |  | $ 727,800,000 |
Financial Instrument, Owned, Pledged Status [Extensible Enumeration] | Securities pledged |  | Securities pledged |
Carrying Amount |  |  |  |
Securities available-for-sale: |  |  |  |
Securities available-for-sale transferred to held-to-maturity | $ 400,000,000.0 |  |  |
Securities held-to-maturity | 591,403,000 |  | $ 179,309,000 |
Fair Value |  |  |  |
Securities available-for-sale: |  |  |  |
Securities available-for-sale transferred to held-to-maturity | 372,200,000 |  |  |
Securities held-to-maturity | 511,054,000 |  | 177,354,000 |
Agency collateralized mortgage obligations ("CMOs") |  |  |  |
Securities available-for-sale: |  |  |  |
Securities held-to-maturity | 189,118,000 |  | 60,054,000 |
Agency Notes |  |  |  |
Securities available-for-sale: |  |  |  |
Securities held-to-maturity | 74,889,000 |  |  |
Pass-through mortgage-backed securities ("MBS") issued by government sponsored entities ("GSEs") |  |  |  |
Securities available-for-sale: |  |  |  |
Securities held-to-maturity | 238,334,000 |  | 117,300,000 |
Available for sale debt securities, unrealized loss position due to credit | $ 252,655,000 |  | $ 427,382,000 |

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