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, 2022	Dec. 31, 2021
Available for sale:
Available-for-sale debt securities, amortized cost basis	$ 218,490	$ 341,628
Gross Unrealized Gain	44	3,388
Gross Unrealized Loss	20,590	2,810
Estimated Fair Value	197,944	342,206
Held to maturity:
Amortized Cost	633,386	184,263
Gross Unrealized Gains	86	8,364
Gross Unrealized Losses	37,628	155
Estimated Fair Value	595,844	192,472
U.S. government agencies
Available for sale:
Available-for-sale debt securities, amortized cost basis		10,013
Gross Unrealized Gain		0
Gross Unrealized Loss		42
Estimated Fair Value		9,971
Held to maturity:
Amortized Cost	9,103
Gross Unrealized Losses	1,277
Estimated Fair Value	7,826
Corporate bonds
Available for sale:
Available-for-sale debt securities, amortized cost basis	35,003	35,080
Gross Unrealized Gain		940
Gross Unrealized Loss	1,893	85
Estimated Fair Value	33,110	35,935
Municipal securities
Available for sale:
Available-for-sale debt securities, amortized cost basis	9,487
Gross Unrealized Gain	33
Gross Unrealized Loss	103
Estimated Fair Value	9,417
Held to maturity:
Amortized Cost	192,101	181,310
Gross Unrealized Gains	86	8,364
Gross Unrealized Losses	10,162	118
Estimated Fair Value	182,025	189,556
Mortgage-backed securities
Available for sale:
Available-for-sale debt securities, amortized cost basis	150,516	221,610
Gross Unrealized Gain	5	1,477
Gross Unrealized Loss	16,906	1,779
Estimated Fair Value	133,615	221,308
Held to maturity:
Amortized Cost	135,292	2,953
Gross Unrealized Gains	0	0
Gross Unrealized Losses	15,743	37
Estimated Fair Value	119,549	2,916
Collateralized mortgage obligations
Available for sale:
Available-for-sale debt securities, amortized cost basis	23,484	74,925
Gross Unrealized Gain	6	971
Gross Unrealized Loss	1,688	904
Estimated Fair Value	21,802	$ 74,992
Held to maturity:
Amortized Cost	43,157
Gross Unrealized Losses	7,037
Estimated Fair Value	36,120
Treasury securities
Held to maturity:
Amortized Cost	253,733
Gross Unrealized Losses	3,409
Estimated Fair Value	$ 250,324

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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