INVESTMENTS - Schedule of Held To Maturity Credit Quality Indicator (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Investment securities held-to-maturity, net	$ 92,173	$ 111,747
State and political subdivisions
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Investment securities held-to-maturity, net	91,673	111,246
State and political subdivisions | A+ rated or higher
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Investment securities held-to-maturity, net	91,673	110,959
State and political subdivisions | Not rated
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Investment securities held-to-maturity, net	0	287
Foreign bonds
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Investment securities held-to-maturity, net	500	501
Foreign bonds | A+ rated or higher
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Investment securities held-to-maturity, net	500	501
Foreign bonds | Not rated
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Investment securities held-to-maturity, net	$ 0	$ 0