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Investment Securities - Additional Information (Details) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2024 USD ($) Position Security | Dec. 31, 2023 USD ($) Position Security
Schedule Of Available For Sale Securities [Line Items] |  |
Tax rate used to calculate tax-equivalent yields (in hundredths) | 21.00% |
Percentage investment book value exceeds stockholders' equity (in hundredths) | 10.00% |
Debt securities, available-for-sale, restricted | $ 633,000 | $ 831,000
Available-for-sale, 12 months or longer, Fair Value | 1,001,277 | 1,075,835
12 months or longer, unrealized losses | $ 193,568 | $ 192,616
U.S. Treasury Securities and Obligations of U.S. Government Corporations and Agencies |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Number of securities in unrealized loss positions | Security | 29 | 36
Available-for-sale, 12 months or longer, Fair Value | $ 189,327 | $ 210,069
12 months or longer, unrealized losses | $ 21,158 | $ 26,215
Held-to-maturity, securities in unrealized loss positions, qualitative disclosure, number of positions | Position | 0 | 0
Obligations of States and Political Subdivisions |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Number of securities in unrealized loss positions | Security | 247 | 237
Available-for-sale, 12 months or longer, Fair Value | $ 241,502 | $ 241,630
12 months or longer, unrealized losses | $ 55,193 | $ 49,038
Mortgage-backed Securities: GSE Residential |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Number of securities in unrealized loss positions | Security | 241 | 263
Available-for-sale, 12 months or longer, Fair Value | $ 511,746 | $ 566,197
12 months or longer, unrealized losses | $ 114,552 | $ 113,007
Other Securities |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Number of securities in unrealized loss positions | Security | 40 | 43
Available-for-sale, 12 months or longer, Fair Value | $ 58,702 | $ 57,939
12 months or longer, unrealized losses | $ 2,665 | $ 4,356

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