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Investment Securities - Narrative (Details) | 3 Months Ended | 8 Months Ended | 9 Months Ended |
--- | --- | --- | --- | ---
Sep. 30, 2022 USD ($) security | Sep. 30, 2021 USD ($) | Sep. 01, 2022 USD ($) | Sep. 30, 2022 USD ($) security | Sep. 30, 2021 USD ($) | Dec. 31, 2021 USD ($)
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |  |
Held-to-maturity, book value |  |  | $ 511,000,000 |  |  |
Fair Value | $ 411,018,000 |  | 477,000,000 | $ 411,018,000 |  |
Available-for-sale to held-to-maturity, transfer unrealized loss |  |  | $ 34,000,000 |  |  |
Proceeds from sales of investment securities, available-for-sale | 44,100,000 | $ 0 |  | 47,175,000 | $ 17,559,000 |
Gross realized gain on sale | 0 | 0 |  | 24,000 | 209,000 |
Gross realized loss on sale | $ 96,000 | $ 0 |  | $ 96,000 | $ 72,000 |
Number of securities that have unrealized losses | security | 272 |  |  | 272 |  |
Number of held to maturity securities that have unrealized losses | security | 161 |  |  | 161 |  |
Securities deemed to be other than temporary |  |  |  | $ 0 |  |
Asset Pledged as Collateral |  |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |  |
Investment securities pledged as collateral | $ 350,100,000 |  |  | $ 350,100,000 |  | $ 247,400,000

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- Definition Amount of unrealized gain (loss) recognized in earnings from transfer of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) to investment in debt security measured at fair value with change in fair value recognized in net income (trading). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27357-111563 + Details
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- Definition Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, 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 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (b)(3) -URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27290-111563 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 4 -Subparagraph (b)(3) -URI https://asc.fasb.org/extlink&oid=124269663&loc=SL82922888-210455 + Details
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- Definition The aggregate fair value as of the balance sheet date of financial instruments and other positions owned by the entity including: (1) mortgages, mortgage-backed and asset backed securities; (2) US government and agency obligations; (3) state and municipal government obligations; (4) other sovereign government debt; (5) corporate obligations; (6) corporate equities; (7) principal investments; (8) derivative contracts; and (9) physical commodities. Includes both pledged and unpledged holdings. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 940 -SubTopic 320 -Section 45 -Paragraph 2 -URI https://asc.fasb.org/extlink&oid=35711157&loc=d3e42546-110969 + Details
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