SECURITIES - Credit Quality Indicators (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Debt and Equity Securities, FV-NI [Line Items]
Amortized Cost	$ 658,524	$ 691,484
Aaa
Debt and Equity Securities, FV-NI [Line Items]
Amortized Cost	435,761	467,736
Aa1/Aa2/Aa3
Debt and Equity Securities, FV-NI [Line Items]
Amortized Cost	137,230	110,854
A1/A2
Debt and Equity Securities, FV-NI [Line Items]
Amortized Cost	33,326	13,757
BBB
Debt and Equity Securities, FV-NI [Line Items]
Amortized Cost	10,000	10,000
Not rated
Debt and Equity Securities, FV-NI [Line Items]
Amortized Cost	$ 42,207	$ 89,137