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v3.23.1

Investment Securities - Additional Information (Details) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2023 USD ($) Security | Dec. 31, 2022 USD ($) Securities Security
Schedule Of Available For Sale Securities [Line Items] |  |
Equity securities, at fair value | $ 362,000 | $ 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 | $ 709,000,000 | 770,000,000
Available-for-sale, 12 months or longer, Fair Value | 1,099,203,000 | 677,083,000
12 months or longer, unrealized losses | $ 192,066,000 | $ 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 | 45 | 16
Available-for-sale, 12 months or longer, Fair Value | $ 220,714,000 | $ 163,520,000
12 months or longer, unrealized losses | $ 29,669,000 | $ 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 | 202 | 36
Available-for-sale, 12 months or longer, Fair Value | $ 212,715,000 | $ 45,419,000
12 months or longer, unrealized losses | $ 53,765,000 | $ 16,624,000
Mortgage-backed Securities: GSE Residential |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Number of securities in unrealized loss positions | Security | 219 | 91
Available-for-sale, 12 months or longer, Fair Value | $ 610,896,000 | $ 461,446,000
12 months or longer, unrealized losses | $ 105,178,000 | $ 96,900,000
Other Securities |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Number of securities in unrealized loss positions | Security | 40 | 5
Available-for-sale, 12 months or longer, Fair Value | $ 54,878,000 | $ 6,698,000
12 months or longer, unrealized losses | $ 3,454,000 | $ 844,000

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