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Fair Value Measurements (Carrying Value and Estimated Fair Value of Financial Instruments) (Details) - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Carrying Amount [Member] |  |
Long-term debt | $ 550,597 | $ 439,540
Carrying Amount [Member] | Seven Point Twenty Five Percent Senior Notes [Member] |  |
Long-term debt | 49,910 | 49,907
Carrying Amount [Member] | Six Point Seventy Percent Senior Notes [Member] |  |
Long-term debt | 99,480 | 99,462
Carrying Amount [Member] | Five Point Eight Hundred Seventy Five Percent Senior Notes [Member] |  |
Long-term debt | 0 | 185,000
Carrying Amount [Member] | Five Point Three Hundred Seventy Five [Member] |  |
Long-term debt | 294,157 | 0
Carrying Amount [Member] | One Point Sixty One Percent Borrowing From Federal Home Loan Bank Due July 21, 2021 [Member] |  |
Long-term debt | 25,000 | 25,000
Carrying Amount [Member] | One Point Fifty Six Percent Borrowing From Federal Home Loan Bank Due August 16, 2021 [Member] |  |
Long-term debt | 25,000 | 25,000
Carrying Amount [Member] | Three Point Zero Three Percent Borrowing From Federal Home Loan Bank Due December 16, 2026 [Member] |  |
Long-term debt | 60,000 | 60,000
Carrying Amount [Member] | Long Term Debt Excluding Issuance Costs [Member] |  |
Long-term debt | 553,547 | 444,369
Carrying Amount [Member] | Unamortized Debt Issuance Costs [Member] |  |
Unamortized Debt Issuance Costs | (3,687) | (4,829)
Carrying Amount [Member] | Finance lease obligation [Member] |  |
Finance Lease, Liability | 737 | 0
Fair Value [Member] |  |
Long-term Debt, Fair Value | 659,272 | 448,622
Fair Value [Member] | Seven Point Twenty Five Percent Senior Notes [Member] |  |
Long-term Debt, Fair Value | 66,365 | 57,032
Fair Value [Member] | Six Point Seventy Percent Senior Notes [Member] |  |
Long-term Debt, Fair Value | 123,104 | 107,075
Fair Value [Member] | Five Point Eight Hundred Seventy Five Percent Senior Notes [Member] |  |
Long-term Debt, Fair Value | 0 | 177,230
Fair Value [Member] | Five Point Three Hundred Seventy Five [Member] |  |
Long-term Debt, Fair Value | 357,025 | 0
Fair Value [Member] | One Point Sixty One Percent Borrowing From Federal Home Loan Bank Due July 21, 2021 [Member] |  |
Long-term Debt, Fair Value | 24,901 | 24,218
Fair Value [Member] | One Point Fifty Six Percent Borrowing From Federal Home Loan Bank Due August 16, 2021 [Member] |  |
Long-term Debt, Fair Value | 24,875 | 24,162
Fair Value [Member] | Three Point Zero Three Percent Borrowing From Federal Home Loan Bank Due December 16, 2026 [Member] |  |
Long-term Debt, Fair Value | $ 63,002 | $ 58,905

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- Definition Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. + 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)(3) -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(a)(16)) -URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910 Reference 3: 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 Reference 4: 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 + Details
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