SECURITIES - Available-for-sale (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Securities available-for-sale:
Amortized Cost	$ 1,048,938	$ 1,071,858
Gross Unrealized Gains	2	59
Gross Unrealized Losses	(122,128)	(121,330)
Fair Value	926,812	950,587
Agency Notes
Securities available-for-sale:
Amortized Cost	10,000
Gross Unrealized Losses	(709)
Fair Value	9,291
Treasury Securities
Securities available-for-sale:
Amortized Cost	246,646	246,899
Gross Unrealized Losses	(16,215)	(19,643)
Fair Value	230,431	227,256
Corporate Securities
Securities available-for-sale:
Amortized Cost	172,626	183,791
Gross Unrealized Gains		57
Gross Unrealized Losses	(28,744)	(17,075)
Fair Value	143,882	166,773
Pass-through mortgage-backed securities ("MBS") issued by government sponsored entities ("GSEs")
Securities available-for-sale:
Amortized Cost	263,194	272,774
Gross Unrealized Losses	(28,120)	(31,534)
Fair Value	235,074	241,240
Agency collateralized mortgage obligations ("CMOs")
Securities available-for-sale:
Amortized Cost	324,394	331,394
Gross Unrealized Gains	2	2
Gross Unrealized Losses	(46,002)	(50,057)
Fair Value	278,394	281,339
State and municipal obligations.
Securities available-for-sale:
Amortized Cost	32,078	37,000
Gross Unrealized Losses	(2,338)	(3,021)
Fair Value	$ 29,740	$ 33,979

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
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Amortized cost excluding accrued interest, before allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
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