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Fair Value Measurements - Changes in Level 3 (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022
Asset-backed Securities |  |
Changes in Level 3 |  |
Beginning balance | $ 15,012 |
Transfers into Level 3 |  | $ 15,012
Transfers out of Level 3 | (14,885) | 15,000
Total gains or losses |  |
Included in earnings (or changes in net assets) | (11) |
Included in other comprehensive income | 226 |
Purchases, issuances, sales, and settlements |  |
Settlements | (342) |
Ending balance |  | 15,012
Collateralized loan obligations. |  |
Changes in Level 3 |  |
Beginning balance | 6,770 |
Transfers into Level 3 |  | 6,770
Transfers out of Level 3 | (6,764) | 6,800
Total gains or losses |  |
Included in other comprehensive income | (6) |
Purchases, issuances, sales, and settlements |  |
Ending balance |  | 6,770
States and political subdivisions |  |
Changes in Level 3 |  |
Beginning balance | 14,229 | 15,236
Total gains or losses |  |
Included in earnings (or changes in net assets) | (134) | (136)
Included in other comprehensive income | 1,010 | (86)
Purchases, issuances, sales, and settlements |  |
Purchases | 782 | 519
Settlements | (558) | (1,304)
Ending balance | 15,329 | 14,229
Mortgage Servicing Rights [Member] |  |
Changes in Level 3 |  |
Beginning balance | 11,189 | 7,097
Total gains or losses |  |
Included in earnings (or changes in net assets) | (924) | 4,106
Purchases, issuances, sales, and settlements |  |
Issuances | 580 | 915
Settlements | (501) | (929)
Ending balance | $ 10,344 | $ 11,189

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- Definition Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-2 + Details
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- Definition Amount of gain (loss) recognized in other comprehensive income (OCI) from asset measured at fair value on recurring basis using unobservable input (level 3). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(1a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-2 + Details
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