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MARKETABLE SECURITIES - Schedule of Amortized Cost and Fair Value of Securities Available for Sale and Held to Maturity Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Available for sale:
Available-for-sale debt securities, amortized cost basis	$ 203,373	$ 208,165
Gross Unrealized Gain	61	330
Gross Unrealized Loss	24,790	19,568
Estimated Fair Value	178,644	188,927
Held to maturity:
Amortized Cost	408,308	509,008
Gross Unrealized Gains	104	658
Gross Unrealized Losses	40,721	34,598
Estimated Fair Value	367,691	475,068
U.S. government agencies
Held to maturity:
Amortized Cost	9,254	9,141
Gross Unrealized Gains		0
Gross Unrealized Losses	1,357	1,259
Estimated Fair Value	7,897	7,882
Corporate bonds
Available for sale:
Available-for-sale debt securities, amortized cost basis	29,902	29,964
Gross Unrealized Gain	0	0
Gross Unrealized Loss	3,353	2,177
Estimated Fair Value	26,549	27,787
Municipal securities
Available for sale:
Available-for-sale debt securities, amortized cost basis	2,322	10,324
Gross Unrealized Gain	42	326
Gross Unrealized Loss	0	8
Estimated Fair Value	2,364	10,642
Held to maturity:
Amortized Cost	168,992	191,680
Gross Unrealized Gains	104	658
Gross Unrealized Losses	9,568	8,285
Estimated Fair Value	159,528	184,053
Mortgage-backed securities
Available for sale:
Available-for-sale debt securities, amortized cost basis	151,424	145,896
Gross Unrealized Gain	19	1
Gross Unrealized Loss	19,302	15,556
Estimated Fair Value	132,141	130,341
Held to maturity:
Amortized Cost	122,231	132,693
Gross Unrealized Gains	0	0
Gross Unrealized Losses	19,631	14,708
Estimated Fair Value	102,600	117,985
Collateralized mortgage obligations
Available for sale:
Available-for-sale debt securities, amortized cost basis	19,725	21,981
Gross Unrealized Gain	0	3
Gross Unrealized Loss	2,135	1,827
Estimated Fair Value	17,590	20,157
Held to maturity:
Amortized Cost	38,524	41,759
Gross Unrealized Losses	8,440	7,425
Estimated Fair Value	30,084	34,334
Treasury securities
Held to maturity:
Amortized Cost	69,307	133,735
Gross Unrealized Losses	1,725	2,921
Estimated Fair Value	$ 67,582	$ 130,814

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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).

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