MARKETABLE SECURITIES - Schedule of Amortized Cost and Fair Value of Securities Available for Sale and Held to Maturity Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Available for sale:
Available-for-sale debt securities, amortized cost basis	$ 193,121	$ 208,165
Gross Unrealized Gain	219	330
Gross Unrealized Loss	19,596	19,568
Estimated Fair Value	173,744	188,927
Held to maturity:
Amortized Cost	476,105	509,008
Gross Unrealized Gains	670	658
Gross Unrealized Losses	32,471	34,598
Estimated Fair Value	444,304	475,068
U.S. government agencies
Held to maturity:
Amortized Cost	9,178	9,141
Gross Unrealized Gains		0
Gross Unrealized Losses	1,166	1,259
Estimated Fair Value	8,012	7,882
Corporate bonds
Available for sale:
Available-for-sale debt securities, amortized cost basis	29,943	29,964
Gross Unrealized Gain	0	0
Gross Unrealized Loss	2,302	2,177
Estimated Fair Value	27,641	27,787
Municipal securities
Available for sale:
Available-for-sale debt securities, amortized cost basis	3,186	10,324
Gross Unrealized Gain	216	326
Gross Unrealized Loss	0	8
Estimated Fair Value	3,402	10,642
Held to maturity:
Amortized Cost	181,986	191,680
Gross Unrealized Gains	670	658
Gross Unrealized Losses	7,575	8,285
Estimated Fair Value	175,081	184,053
Mortgage-backed securities
Available for sale:
Available-for-sale debt securities, amortized cost basis	139,187	145,896
Gross Unrealized Gain	0	1
Gross Unrealized Loss	15,609	15,556
Estimated Fair Value	123,578	130,341
Held to maturity:
Amortized Cost	130,138	132,693
Gross Unrealized Gains	0	0
Gross Unrealized Losses	14,726	14,708
Estimated Fair Value	115,412	117,985
Collateralized mortgage obligations
Available for sale:
Available-for-sale debt securities, amortized cost basis	20,805	21,981
Gross Unrealized Gain	3	3
Gross Unrealized Loss	1,685	1,827
Estimated Fair Value	19,123	20,157
Held to maturity:
Amortized Cost	40,864	41,759
Gross Unrealized Losses	7,089	7,425
Estimated Fair Value	33,775	34,334
Treasury securities
Held to maturity:
Amortized Cost	113,939	133,735
Gross Unrealized Losses	1,915	2,921
Estimated Fair Value	$ 112,024	$ 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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