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Statements of Cash Flows (Cash Flow Supplemental Disclosures) (Details) - USD ($) $ in Thousands | 9 Months Ended
--- | ---
Sep. 30, 2019 | Sep. 30, 2018
Interest Paid, Excluding Capitalized Interest, Operating Activities |  | $ 19,261 | $ 15,449
Federal income tax |  | 42,000 | 7,193
Operating cash flows from operating leases | [1] | 6,062 | 0
Operating cash flows from financing leases |  | 12 | 0
Financing cash flows from finance leases |  | 811 | 4,891
Assets acquired under finance lease arrangements |  | 824 |
Assets acquired under finance lease arrangements |  |  | 4,114
Assets acquired under operating lease arrangements | [1] | 13,648 | 0
Non-cash purchase of property and equipment |  | 108 | 0
AFS Fixed Income Securities [Member] |  |  |
Corporate actions related to securities | [2] | 29,771 | 32,757
Equity Securities [Member] |  |  |
Corporate actions related to securities | [2] | $ 14,250 | $ 944
[1] | Upon adoption of ASU 2016-02, effective January 1, 2019, we are required to disclose cash paid for amounts included in the measurement of operating lease liabilities, as well as supplemental non-cash information on operating lease liabilities arising from obtaining operating lease assets.
[2] | Examples of such corporate actions include exchanges, non-cash acquisitions, and stock splits.

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