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Investment Securities - Additional Information (Details) | 12 Months Ended |
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Dec. 31, 2022 USD ($) Position Security | Dec. 31, 2021 USD ($) Position Security
Schedule Of Available For Sale Securities [Line Items] |  |
Equity securities, at fair value | $ 311,000 | $ 397,000
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 | $ 770,000,000 | 590,000,000
Available-for-sale, 12 months or longer, Fair Value | 677,083,000 | 186,350,000
12 months or longer, unrealized losses | $ 143,282,000 | $ 4,627,000
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 | 16 | 6
Available-for-sale, 12 months or longer, Fair Value | $ 163,520,000 | $ 139,846,000
12 months or longer, unrealized losses | $ 28,914,000 | $ 2,936,000
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 | 36 | 0
Available-for-sale, 12 months or longer, Fair Value | $ 45,419,000 | $ 0
12 months or longer, unrealized losses | $ 16,624,000 | $ 0
Mortgage-backed Securities: GSE Residential |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Number of securities in unrealized loss positions | Security | 91 | 15
Available-for-sale, 12 months or longer, Fair Value | $ 461,446,000 | $ 46,504,000
12 months or longer, unrealized losses | $ 96,900,000 | $ 1,691,000
Other Securities |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Number of securities in unrealized loss positions | Security | 5 | 0
Available-for-sale, 12 months or longer, Fair Value | $ 6,698,000 | $ 0
12 months or longer, unrealized losses | $ 844,000 | $ 0

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