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Indebtedness Indebtedness (Schedule of Long-Term Debt) (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Schedule of Debt Instruments [Line Items] |  |
Long-term debt | $ 550,743 | $ 550,597
Unamortized Debt Issuance Costs | 3,419 |
Unamortized Debt Discount | 6,346 |
Finance Lease, Liability | $ 508 | 737
Five Point Three Hundred Seventy Five [Member] |  |
Schedule of Debt Instruments [Line Items] |  |
Interest Rate | 5.375% |
Long-term Debt, Gross | $ 300,000 |
Unamortized Debt Issuance Costs | 2,934 |
Unamortized Debt Discount | 5,759 |
Long-term Debt | $ 291,307 | 291,010
Five Point Eight Hundred Seventy Five Percent Senior Notes [Member] |  |
Schedule of Debt Instruments [Line Items] |  |
Interest Rate | 5.875% |
Long-term Debt, Gross | $ 185,000 |
Three Point Zero Three Percent Borrowing From Federal Home Loan Bank Due December 16, 2026 [Member] |  |
Schedule of Debt Instruments [Line Items] |  |
Interest Rate | 3.03% |
Long-term Debt, Gross | $ 60,000 |
Unamortized Debt Issuance Costs | 0 |
Unamortized Debt Discount | 0 |
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] |  |
Interest Rate | 1.56% |
Long-term Debt, Gross | $ 25,000 |
Unamortized Debt Issuance Costs | 0 |
Unamortized Debt Discount | 0 |
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] |  |
Interest Rate | 1.61% |
Long-term Debt, Gross | $ 25,000 |
Unamortized Debt Issuance Costs | 0 |
Unamortized Debt Discount | 0 |
Long-term Debt | $ 25,000 | 25,000
Six Point Seventy Percent Senior Notes [Member] |  |
Schedule of Debt Instruments [Line Items] |  |
Interest Rate | 6.70% |
Long-term Debt, Gross | $ 100,000 |
Unamortized Debt Issuance Costs | 319 |
Unamortized Debt Discount | 501 |
Long-term Debt | $ 99,180 | 99,125
Seven Point Twenty Five Percent Senior Notes [Member] |  |
Schedule of Debt Instruments [Line Items] |  |
Interest Rate | 7.25% |
Long-term Debt, Gross | $ 50,000 |
Unamortized Debt Issuance Costs | 166 |
Unamortized Debt Discount | 86 |
Long-term Debt | 49,748 | 49,725
Finance lease obligation [Member] |  |
Schedule of Debt Instruments [Line Items] |  |
Finance Lease, Liability | $ 508 | $ 737

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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=120520924&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=120400017&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=120391452&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=120398452&loc=d3e534808-122878 + Details
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