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Statements of Cash Flow (Cash Flow Supplemental Disclosures) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Interest | $ 28,930 | $ 30,464 | $ 25,089
Federal income tax | 100,000 | 47,000 | 55,825
Operating cash flows from operating leases | 7,935 | 9,498 | 8,138
Operating cash flows from financing leases | 35 | 15 | 16
Financing cash flows from financing leases | 1,768 | 550 | 977
Assets acquired under finance lease arrangements | 6,709 | 324 | 824
Assets acquired under operating lease arrangements | 3,272 | 22,390 | 13,808
Non-cash purchase of property and equipment | 472 | 590 | 89
Available-for-sale Securities [Member] |  |  |
Corporate actions related to securities | 56,365 | 55,446 | 61,369
Held-to-maturity Securities [Member] |  |  |
Corporate actions related to securities | 0 | 2,589 | 0
Equity Securities [Member] |  |  |
Corporate actions related to securities | 30,666 | 10,890 | 14,250
Conversion of AFS fixed income securities to equity securities | $ 15,139 | $ 0 | $ 0

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- Definition Amount of cash paid for interest, including, but not limited to, capitalized interest and payment to settle zero-coupon bond attributable to accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount; classified as operating and investing activities. + References No definition available. + Details
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- Definition Amount of interest paid on finance lease liability. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (g)(1) -URI http://asc.fasb.org/extlink&oid=123408670&loc=SL77918686-209980 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 5 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918643-209977 + Details
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- Definition Amount of cash outflow for principal payment on finance lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 5 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918643-209977 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (g)(1) -URI http://asc.fasb.org/extlink&oid=123408670&loc=SL77918686-209980 + Details
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- Definition The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=123431023&loc=d3e4297-108586 + Details
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