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Statements of Cash Flow (Cash Flow Supplemental Disclosures) (Details) - USD ($) $ in Thousands | 9 Months Ended
--- | ---
Sep. 30, 2015 | Sep. 30, 2014
Interest |  | $ 13,843 | $ 14,089
Federal income tax |  | 18,500 | 4,699
Corporate actions related to equity securities, AFS | [1] | 4,239 | 334
Assets acquired under capital lease arrangements |  | 6,933 | 4,853
AFS Fixed Maturity Securities [Member] |  |  |
Tax-free exchange of fixed maturity securities |  | 35,425 | 14,954
Held-to-maturity Securities [Member] |  |  |
Tax-free exchange of fixed maturity securities |  | 10,045 | 4,288
National Flood Insurance Program [Member] |  |  |
Restricted Cash |  | $ 9,900 | $ 8,100
[1] | 1Examples of such corporate actions include non-cash acquisitions and stock splits.

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- Definition The increase during the period in capital lease obligations due to entering into new capital leases. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4313-108586 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586 + Details
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- Definition The value of the stock converted in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period 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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4313-108586 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4332-108586 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586 + Details
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