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Statements of Cash Flow (Cash Flow Supplemental Disclosures) (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2019 | Mar. 31, 2018
Interest |  | $ 4,477 | $ 3,455
Federal income tax |  | 0 | (2,807)
Operating cash flows from operating leases | [1] | 1,983 | 0
Financing cash flows from finance leases |  | 284 |
Repayments of capital lease obligations |  |  | 734
Assets acquired under operating lease arrangements | [1] | 6,136 | 0
Non-cash purchase of property and equipment |  | 162 | 0
AFS Fixed Income Securities [Member] |  |  |
Corporate actions related to securities | [2] | $ 18,447 | $ 11,347
[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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- 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=98513485&loc=d3e4297-108586 + Details
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- Definition The amount of fixed assets that an Entity acquires in a noncash (or part noncash) acquisition. Noncash is defined as information about all investing and financing activities of an enterprise during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4332-108586 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4313-108586 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586 + Details
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