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v3.23.2

Investment Securities - Additional Information (Details) | 6 Months Ended |
--- | --- | ---
Jun. 30, 2023 USD ($) Security | Dec. 31, 2022 USD ($) Securities Security
Schedule Of Available For Sale Securities [Line Items] |  |
Equity securities, at fair value | $ 409,000 | $ 311,000
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 | $ 904,000,000 | 770,000,000
Available-for-sale, 12 months or longer, Fair Value | 1,092,621,000 | 677,083,000
12 months or longer, unrealized losses | $ 211,927,000 | $ 143,282,000
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 | 43 | 16
Available-for-sale, 12 months or longer, Fair Value | $ 213,600,000 | $ 163,520,000
12 months or longer, unrealized losses | $ 31,540,000 | $ 28,914,000
Held-to-maturity, securities in unrealized loss positions, qualitative disclosure, number of positions | Securities |  | 0
Obligations of States and Political Subdivisions |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Number of securities in unrealized loss positions | Security | 225 | 36
Available-for-sale, 12 months or longer, Fair Value | $ 230,437,000 | $ 45,419,000
12 months or longer, unrealized losses | $ 55,831,000 | $ 16,624,000
Mortgage-backed Securities: GSE Residential |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Number of securities in unrealized loss positions | Security | 251 | 91
Available-for-sale, 12 months or longer, Fair Value | $ 590,760,000 | $ 461,446,000
12 months or longer, unrealized losses | $ 119,552,000 | $ 96,900,000
Other Securities |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Number of securities in unrealized loss positions | Security | 42 | 5
Available-for-sale, 12 months or longer, Fair Value | $ 57,824,000 | $ 6,698,000
12 months or longer, unrealized losses | $ 5,004,000 | $ 844,000

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