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Investment Securities - Additional Information (Details) | 6 Months Ended |
--- | --- | ---
Jun. 30, 2022 USD ($) Security | Dec. 31, 2021 USD ($) Security
Schedule Of Available For Sale Securities [Line Items] |  |
Equity securities, at fair value | $ 308,000 | $ 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 | $ 724,000,000 | 590,000,000
Available-for-sale, 12 months or longer, Fair Value | 310,522,000 | 186,350,000
12 months or longer, unrealized losses | $ 51,516,000 | $ 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 | 14 | 6
Available-for-sale, 12 months or longer, Fair Value | $ 111,991,000 | $ 139,846,000
12 months or longer, unrealized losses | $ 15,618,000 | $ 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 | 5 | 0
Available-for-sale, 12 months or longer, Fair Value | $ 7,466,000 | $ 0
12 months or longer, unrealized losses | $ 2,626,000 | $ 0
Mortgage-backed Securities: GSE Residential |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Number of securities in unrealized loss positions | Security | 42 | 15
Available-for-sale, 12 months or longer, Fair Value | $ 188,576,000 | $ 46,504,000
12 months or longer, unrealized losses | $ 33,196,000 | $ 1,691,000
Other Securities |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Number of securities in unrealized loss positions | Security | 3 | 0
Available-for-sale, 12 months or longer, Fair Value | $ 2,489,000 | $ 0
12 months or longer, unrealized losses | $ 76,000 | $ 0

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