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v3.22.2.2

Investment Securities - Additional Information (Details) | 9 Months Ended |
--- | --- | ---
Sep. 30, 2022 USD ($) Security | Dec. 31, 2021 USD ($) Security
Schedule Of Available For Sale Securities [Line Items] |  |
Equity securities, at fair value | $ 317,000 | $ 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 | $ 818,000,000 | 590,000,000
Available-for-sale, 12 months or longer, Fair Value | 554,983,000 | 186,350,000
12 months or longer, unrealized losses | $ 126,058,000 | $ 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 | $ 132,392,000 | $ 139,846,000
12 months or longer, unrealized losses | $ 25,129,000 | $ 2,936,000
Held-to-maturity, securities in unrealized loss positions, qualitative disclosure, number of positions | Security |  | 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 | $ 37,212,000 | $ 0
12 months or longer, unrealized losses | $ 17,340,000 | $ 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 | $ 379,400,000 | $ 46,504,000
12 months or longer, unrealized losses | $ 83,018,000 | $ 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 | $ 5,979,000 | $ 0
12 months or longer, unrealized losses | $ 571,000 | $ 0

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