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Investment Securities - Additional Information (Details) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2022 USD ($) Security | Dec. 31, 2021 USD ($) Security
Schedule Of Available For Sale Securities [Line Items] |  |
Equity securities, at fair value | $ 369,000 | $ 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 | $ 665,000,000 | 590,000,000
Available-for-sale, 12 months or longer, Fair Value | 319,139,000 | 186,350,000
12 months or longer, unrealized losses | $ 34,538,000 | $ 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 | $ 116,577,000 | $ 139,846,000
12 months or longer, unrealized losses | $ 11,117,000 | $ 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 | $ 6,399,000 | $ 0
12 months or longer, unrealized losses | $ 1,241,000 | $ 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 | $ 193,648,000 | $ 46,504,000
12 months or longer, unrealized losses | $ 22,122,000 | $ 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 | $ 2,515,000 | $ 0
12 months or longer, unrealized losses | $ 58,000 | $ 0

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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=124269663&loc=SL82922890-210455 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27337-111563 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=121590138&loc=SL82922954-210456 + Details
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