Investment Securities - Amortized Cost of Debt Securities Held-to-Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Securities held to maturity	$ 139,058	$ 160,983
AAA/AA/A
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Securities held to maturity	139,058	160,983
BBB/BB/B
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Securities held to maturity	0	0
Obligations of U.S. government agencies | AAA/AA/A
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Securities held to maturity	136,398	154,830
Obligations of U.S. government agencies | BBB/BB/B
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Securities held to maturity	0	0
Obligations of states and political subdivisions
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Securities held to maturity	2,660	6,153
Obligations of states and political subdivisions | AAA/AA/A
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Securities held to maturity	2,660	6,153
Obligations of states and political subdivisions | BBB/BB/B
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Securities held to maturity	$ 0	$ 0