FAIR VALUE MEASUREMENTS, Assets and Liabilities Measured at Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Assets Recorded at Fair Value on a Recurring Basis [Abstract]
Total investments at fair value	$ 623,795	$ 618,092
Recurring [Member]
Assets Recorded at Fair Value on a Recurring Basis [Abstract]
Total investments at fair value	623,795	618,092
Liabilities Recorded at Fair Value [Abstract]
Liabilities	0	0
Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Assets Recorded at Fair Value on a Recurring Basis [Abstract]
Total investments at fair value	111,880	113,815
Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member]
Assets Recorded at Fair Value on a Recurring Basis [Abstract]
Total investments at fair value	511,915	504,277
Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member]
Assets Recorded at Fair Value on a Recurring Basis [Abstract]
Total investments at fair value	0	0
Non-recurring [Member]
Assets Recorded at Fair Value on a Non-Recurring Basis [Abstract]
Assets at fair value	0	0
Liabilities Recorded at Fair Value [Abstract]
Liabilities	0	0
U.S. Treasury Securities [Member]
Assets Recorded at Fair Value on a Recurring Basis [Abstract]
Total investments at fair value	111,880	113,815
U.S. Treasury Securities [Member] | Recurring [Member]
Assets Recorded at Fair Value on a Recurring Basis [Abstract]
Total investments at fair value	111,880	113,815
U.S. Treasury Securities [Member] | Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Assets Recorded at Fair Value on a Recurring Basis [Abstract]
Total investments at fair value	111,880	113,815
U.S. Treasury Securities [Member] | Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member]
Assets Recorded at Fair Value on a Recurring Basis [Abstract]
Total investments at fair value	0	0
U.S. Treasury Securities [Member] | Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member]
Assets Recorded at Fair Value on a Recurring Basis [Abstract]
Total investments at fair value	0	0
Securities of U.S. Government Agencies and Corporations [Member]
Assets Recorded at Fair Value on a Recurring Basis [Abstract]
Total investments at fair value	113,499	118,911
Securities of U.S. Government Agencies and Corporations [Member] | Recurring [Member]
Assets Recorded at Fair Value on a Recurring Basis [Abstract]
Total investments at fair value	113,499	118,911
Securities of U.S. Government Agencies and Corporations [Member] | Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Assets Recorded at Fair Value on a Recurring Basis [Abstract]
Total investments at fair value	0	0
Securities of U.S. Government Agencies and Corporations [Member] | Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member]
Assets Recorded at Fair Value on a Recurring Basis [Abstract]
Total investments at fair value	113,499	118,911
Securities of U.S. Government Agencies and Corporations [Member] | Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member]
Assets Recorded at Fair Value on a Recurring Basis [Abstract]
Total investments at fair value	0	0
Obligations of States and Political Subdivisions [Member]
Assets Recorded at Fair Value on a Recurring Basis [Abstract]
Total investments at fair value	54,623	53,326
Obligations of States and Political Subdivisions [Member] | Recurring [Member]
Assets Recorded at Fair Value on a Recurring Basis [Abstract]
Total investments at fair value	54,623	53,326
Obligations of States and Political Subdivisions [Member] | Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Assets Recorded at Fair Value on a Recurring Basis [Abstract]
Total investments at fair value	0	0
Obligations of States and Political Subdivisions [Member] | Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member]
Assets Recorded at Fair Value on a Recurring Basis [Abstract]
Total investments at fair value	54,623	53,326
Obligations of States and Political Subdivisions [Member] | Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member]
Assets Recorded at Fair Value on a Recurring Basis [Abstract]
Total investments at fair value	0	0
Collateralized Mortgage Obligations [Member]
Assets Recorded at Fair Value on a Recurring Basis [Abstract]
Total investments at fair value	100,743	95,350
Collateralized Mortgage Obligations [Member] | Recurring [Member]
Assets Recorded at Fair Value on a Recurring Basis [Abstract]
Total investments at fair value	100,743	95,350
Collateralized Mortgage Obligations [Member] | Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Assets Recorded at Fair Value on a Recurring Basis [Abstract]
Total investments at fair value	0	0
Collateralized Mortgage Obligations [Member] | Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member]
Assets Recorded at Fair Value on a Recurring Basis [Abstract]
Total investments at fair value	100,743	95,350
Collateralized Mortgage Obligations [Member] | Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member]
Assets Recorded at Fair Value on a Recurring Basis [Abstract]
Total investments at fair value	0	0
Mortgage-backed Securities [Member]
Assets Recorded at Fair Value on a Recurring Basis [Abstract]
Total investments at fair value	243,050	236,690
Mortgage-backed Securities [Member] | Recurring [Member]
Assets Recorded at Fair Value on a Recurring Basis [Abstract]
Total investments at fair value	243,050	236,690
Mortgage-backed Securities [Member] | Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Assets Recorded at Fair Value on a Recurring Basis [Abstract]
Total investments at fair value	0	0
Mortgage-backed Securities [Member] | Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member]
Assets Recorded at Fair Value on a Recurring Basis [Abstract]
Total investments at fair value	243,050	236,690
Mortgage-backed Securities [Member] | Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member]
Assets Recorded at Fair Value on a Recurring Basis [Abstract]
Total investments at fair value	$ 0	$ 0