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Indebtedness Indebtedness (Schedule of Long-Term Debt) (Details) - USD ($) $ in Thousands | Dec. 31, 2018 | Dec. 31, 2017
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Three Point Zero Three Percent Borrowing From Federal Home Loan Bank Due December 16, 2026 [Member] |  |
Schedule of Debt Instruments [Line Items] |  |
Debt Discount and Unamortized Issuance Costs | $ 0 |
Interest Rate | 3.03% |
Long-term Debt, Gross | $ 60,000 |
Long-term Debt | 60,000 | $ 60,000
One Point Fifty Six Percent Borrowing From Federal Home Loan Bank Due August 16, 2021 [Member] |  |
Schedule of Debt Instruments [Line Items] |  |
Debt Discount and Unamortized Issuance Costs | $ 0 |
Interest Rate | 1.56% |
Long-term Debt, Gross | $ 25,000 |
Long-term Debt | 25,000 | 25,000
One Point Sixty One Percent Borrowing From Federal Home Loan Bank Due July 21, 2021 [Member] |  |
Schedule of Debt Instruments [Line Items] |  |
Debt Discount and Unamortized Issuance Costs | $ 0 |
Interest Rate | 1.61% |
Long-term Debt, Gross | $ 25,000 |
Long-term Debt | 25,000 | 25,000
Five Point Eight Hundred Seventy Five Percent Senior Notes [Member] |  |
Schedule of Debt Instruments [Line Items] |  |
Debt Discount and Unamortized Issuance Costs | $ (4,229) |
Interest Rate | 5.875% |
Long-term Debt, Gross | $ 185,000 |
Long-term Debt | 180,771 | 180,430
Six Point Seventy Percent Senior Notes [Member] |  |
Schedule of Debt Instruments [Line Items] |  |
Debt Discount and Unamortized Issuance Costs | $ (931) |
Interest Rate | 6.70% |
Long-term Debt, Gross | $ 100,000 |
Long-term Debt | 99,069 | 99,011
Seven Point Twenty Five Percent Senior Notes [Member] |  |
Schedule of Debt Instruments [Line Items] |  |
Debt Discount and Unamortized Issuance Costs | $ (300) |
Interest Rate | 7.25% |
Long-term Debt, Gross | $ 50,000 |
Long-term Debt | 49,700 | 49,675
Long-term Debt [Member] |  |
Schedule of Debt Instruments [Line Items] |  |
Debt Discount and Unamortized Issuance Costs | (5,460) |
Long-term Debt, Gross | 445,000 |
Long-term Debt | $ 439,540 | $ 439,116

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- Definition Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6031897-161870 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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