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The amount of securities transferred to held to maturity.

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Threshold percentage which the entity uses for disclosure.

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Represents the number of share transfers of securities held-to-maturity to securities available-for-sale.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position without allowance for credit loss.

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

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Amount, after tax, of adjustment from accumulated other comprehensive income (loss) for amortization of gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) from transfer to investment in debt security measured at amortized cost (held-to-maturity).

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SECURITIES - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
SECURITIES - Narrative (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Securities available-for-sale:
Securities available-for-sale transferred to held-to-maturity	$ 175,260
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	$ 358,689		$ 177,354
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
Accrued interest receivable on securities	4,500		$ 4,400
Unrealized loss on transfer of securities to held to maturity	6,800
Gain (loss) on transfer of securities to held-to-maturity	0
Carrying Amount
Securities available-for-sale:
Securities available-for-sale transferred to held-to-maturity	182,100
Securities held-to-maturity	383,922		179,309
Fair Value
Securities available-for-sale:
Securities available-for-sale transferred to held-to-maturity	175,300
Securities held-to-maturity	358,689		177,354
Available-for-sale Securities
Securities available-for-sale:
Securities pledged as collateral, carrying amount	451,400		595,800
Held-to-maturity Securities
Securities available-for-sale:
Securities pledged as collateral, carrying amount	352,400		132,000
Agency collateralized mortgage obligations ("CMOs")
Securities available-for-sale:
Securities held-to-maturity	107,980		60,054
Agency Notes
Securities available-for-sale:
Securities held-to-maturity	83,833
Pass-through mortgage-backed securities ("MBS") issued by government sponsored entities ("GSEs")
Securities available-for-sale:
Securities held-to-maturity	166,876		117,300
Available for sale debt securities, unrealized loss position due to credit	$ 360,633		$ 427,382