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Fair Value Measurements - Changes in Level 3 (Details) - USD ($) $ in Thousands | 9 Months Ended
--- | ---
Sep. 30, 2022 | Sep. 30, 2021
States and political subdivisions |  |
Changes in Level 3 |  |
Beginning balance | $ 15,236 | $ 4,319
Total gains or losses |  |
Included in earnings (or changes in net assets) |  | (7)
Included in other comprehensive income (loss) | (1,333) | 812
Purchases, issuances, sales, and settlements |  |
Purchases |  | 748
Issuances | 519 |
Settlements | (1,015) | (312)
Ending balance | 13,309 | 5,560
Changes in Level 3 (liabilities) |  |
Included in earnings (or changes in net assets) | (98) |
Mortgage Servicing Rights [Member] |  |
Changes in Level 3 |  |
Beginning balance | 7,097 | 4,224
Total gains or losses |  |
Included in earnings (or changes in net assets) |  | 840
Purchases, issuances, sales, and settlements |  |
Issuances | 756 | 1,298
Settlements | (776) | (1,042)
Ending balance | 11,461 | $ 5,320
Changes in Level 3 (liabilities) |  |
Included in earnings (or changes in net assets) | $ 4,384 |

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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 -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258 + 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 -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1a) -URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258 + Details
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