MARKETABLE SECURITIES - Schedule of Amortized Cost and Fair Value of Securities Available for Sale and Held to Maturity Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Available for sale:
Available-for-sale debt securities, amortized cost basis	$ 187,959	$ 208,165
Gross Unrealized Gain	120	330
Gross Unrealized Loss	21,483	19,568
Estimated Fair Value	166,596	188,927
Held to maturity:
Amortized Cost	437,292	509,008
Gross Unrealized Gains	451	658
Gross Unrealized Losses	35,008	34,598
Estimated Fair Value	402,735	475,068
U.S. government agencies
Held to maturity:
Amortized Cost	9,216	9,141
Gross Unrealized Gains		0
Gross Unrealized Losses	1,235	1,259
Estimated Fair Value	7,981	7,882
Corporate bonds
Available for sale:
Available-for-sale debt securities, amortized cost basis	29,923	29,964
Gross Unrealized Gain	0	0
Gross Unrealized Loss	3,133	2,177
Estimated Fair Value	26,790	27,787
Municipal securities
Available for sale:
Available-for-sale debt securities, amortized cost basis	2,323	10,324
Gross Unrealized Gain	119	326
Gross Unrealized Loss	0	8
Estimated Fair Value	2,442	10,642
Held to maturity:
Amortized Cost	174,273	191,680
Gross Unrealized Gains	451	658
Gross Unrealized Losses	8,149	8,285
Estimated Fair Value	166,575	184,053
Mortgage-backed securities
Available for sale:
Available-for-sale debt securities, amortized cost basis	137,875	145,896
Gross Unrealized Gain	0	1
Gross Unrealized Loss	16,435	15,556
Estimated Fair Value	121,440	130,341
Held to maturity:
Amortized Cost	125,005	132,693
Gross Unrealized Gains	0	0
Gross Unrealized Losses	15,734	14,708
Estimated Fair Value	109,271	117,985
Collateralized mortgage obligations
Available for sale:
Available-for-sale debt securities, amortized cost basis	17,838	21,981
Gross Unrealized Gain	1	3
Gross Unrealized Loss	1,915	1,827
Estimated Fair Value	15,924	20,157
Held to maturity:
Amortized Cost	39,667	41,759
Gross Unrealized Losses	7,762	7,425
Estimated Fair Value	31,905	34,334
Treasury securities
Held to maturity:
Amortized Cost	89,131	133,735
Gross Unrealized Losses	2,128	2,921
Estimated Fair Value	$ 87,003	$ 130,814

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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