SECURITIES - Held-to-maturity Debt Securities with Unrealized Loss Position (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Less than 12 Months
Fair Value	$ 0	$ 167,688
Unrealized Loss	0	(12,316)
12 Months or More
Fair Value	352,069	199,700
Unrealized Loss	(39,232)	(25,061)
Fair Value	352,069	367,388
Unrealized Loss	(39,232)	(37,377)
Credit related impairment	0	0
U.S. Government sponsored entities
Less than 12 Months
Fair Value	0	143,556
Unrealized Loss	0	(10,063)
12 Months or More
Fair Value	276,243	136,879
Unrealized Loss	(26,628)	(17,213)
Fair Value	276,243	280,435
Unrealized Loss	(26,628)	(27,276)
Residential & multi-family mortgage
Less than 12 Months
Fair Value	0	24,132
Unrealized Loss	0	(2,253)
12 Months or More
Fair Value	75,826	62,821
Unrealized Loss	(12,604)	(7,848)
Fair Value	75,826	86,953
Unrealized Loss	$ (12,604)	$ (10,101)

Debt Securities, Held-to-maturity, Unrealized Loss Position Less Than 12 Months [Abstract]

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Debt Securities, Held-to-maturity, Unrealized Loss Position More Than 12 Months [Abstract]

+ References

No definition available.

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- Definition

Amount of allowance for credit loss for debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
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-Topic 326
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-Topic 326
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Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity), in continuous loss position for 12 months or longer.

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-Topic 320
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Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity), in unrealized loss position.

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

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