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Statements of Cash Flows (Cash Flow Supplemental Disclosures) (Details) - USD ($) $ in Thousands | 6 Months Ended
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Jun. 30, 2022 | Jun. 30, 2021
Interest |  | $ 14,240 | $ 14,547
Federal income tax |  | 40,200 | 66,000
Operating cash flows from operating leases |  | 4,086 | 4,348
Operating cash flows from financing leases |  | 20 | 4
Financing cash flows from finance leases |  | 1,202 | 229
Assets acquired under finance lease arrangements |  | 41 | 183
Assets acquired under operating lease arrangements |  | 5,781 | 16
Non-cash purchase of property and equipment |  | 17 | 35
Available-for-sale Securities |  |  |
Corporate actions related to securities | [1] | 17,287 | 45,392
Equity Securities [Member] |  |  |
Corporate actions related to securities | [1] | 0 | $ 527
Conversion of AFS fixed income securities to equity securities |  | $ 1,463 |
[1] | Examples of corporate actions include like-kind exchanges, non-cash acquisitions, and stock splits.

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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 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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