MARKETABLE SECURITIES - Investments Classified by Contractual Maturity Date (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Amortized Cost
Due within one year	$ 0
Due after one year through five years	9,556
Due after five years through ten years	20,367
Due after ten years	2,323
Available-for-sale debt securities, amortized cost basis	187,959	$ 208,165
Estimated Fair Value
Due within one year	0
Due after one year through five years	9,104
Due after five years through ten years	17,686
Due after ten years	2,442
Available-for-sale debt securities, estimated fair value	166,596	188,927
Held to Maturity Amortized Cost
Due within one year	66,242
Due after one year through five years	67,339
Due after five years through ten years	80,604
Due after ten years	58,435
Held to Maturity debt securities, amortized cost	437,292	509,008
Held to Maturity Estimated Fair Value
Due within one year	65,078
Due after one year through five years	64,222
Due after five years through ten years	77,506
Due after ten years	54,753
Held to maturity debt securities, estimated fair value	402,735	475,068
Mortgage-backed securities
Amortized Cost
Available-for-sale debt securities, amortized cost basis	137,875
Available-for-sale debt securities, amortized cost basis	137,875	145,896
Estimated Fair Value
Available-for-sale debt securities, estimated fair value	121,440
Available-for-sale debt securities, estimated fair value	121,440	130,341
Held to Maturity Amortized Cost
Held to Maturity debt securities, amortized cost	125,005
Held to Maturity debt securities, amortized cost	125,005	132,693
Held to Maturity Estimated Fair Value
Held to maturity debt securities, estimated fair value	109,271
Held to maturity debt securities, estimated fair value	109,271	117,985
Collateralized mortgage obligations
Amortized Cost
Available-for-sale debt securities, amortized cost basis	17,838
Available-for-sale debt securities, amortized cost basis	17,838	21,981
Estimated Fair Value
Available-for-sale debt securities, estimated fair value	15,924
Available-for-sale debt securities, estimated fair value	15,924	20,157
Held to Maturity Amortized Cost
Held to Maturity debt securities, amortized cost	39,667
Held to Maturity debt securities, amortized cost	39,667	41,759
Held to Maturity Estimated Fair Value
Held to maturity debt securities, estimated fair value	31,905
Held to maturity debt securities, estimated fair value	$ 31,905	$ 34,334