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Fair Value of Assets and Liabilities - Fair Value of Assets Measured on a Recurring Basis Using Significant Unobservable Inputs (Details) - Obligations of States and Political Subdivisions - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Beginning balance | $ 615 | $ 792 | $ 794 | $ 973
Transfers into Level 3 | 0 | 0 | 0 | 0
Transfers out of Level 3 | 0 | 0 | 0 | 0
Total gains or losses: |  |  |  |
Included in net income | 1 | 1 | 3 | 4
Included in other comprehensive income (loss) | 0 | 0 | 0 | 0
Purchases, issuances, sales and settlements: |  |  |  |
Purchases | 0 | 0 | 0 | 0
Issuances | 0 | 0 | 0 | 0
Sales | 0 | 0 | 0 | 0
Settlements | 0 | 0 | (181) | (184)
Ending balance | 616 | 793 | 616 | 793
Total gains or losses for the period included in net income attributable to the change in unrealized gains or losses related to assets and liabilities still held at the reporting date | $ 0 | $ 0 | $ 0 | $ 0

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- Definition Amount of unrealized gain (loss) recognized in income from asset (liability) measured at fair value on recurring basis using unobservable input (level 3) and still held. + 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 (d) -URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258 + Details
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
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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 http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258 + Details
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