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Long-Term Debt Senior Notes (Details) - USD ($) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2016 | Mar. 31, 2015 | Dec. 31, 2015
Debt Instrument [Line Items] |  |  |
Debt Instrument, Face Amount | $ 2,303,736,000 |  | $ 2,350,000,000
Unamortized Debt Issuance Expense | 32,264,000 |  | 34,030,000
Senior Notes, Noncurrent | 2,271,472,000 |  | 2,315,970,000
Gain (Loss) on Extinguishment of Debt | 15,722,000 | $ 0 |
6.50% Senior Notes Due 2021 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Face Amount | 346,955,000 |  | 350,000,000
Unamortized Debt Issuance Expense | 3,896,000 |  | 4,106,000
Senior Notes, Noncurrent | 343,059,000 |  | 345,894,000
6.125% Senior Notes Due 2022 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Face Amount | 561,796,000 |  | 600,000,000
Unamortized Debt Issuance Expense | 7,863,000 |  | 8,714,000
Senior Notes, Noncurrent | 553,933,000 |  | 591,286,000
6.50% Senior Notes Due 2023 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Face Amount | 394,985,000 |  | 400,000,000
Unamortized Debt Issuance Expense | 4,983,000 |  | 5,231,000
Senior Notes, Noncurrent | 390,002,000 |  | 394,769,000
5% Senior Notes Due 2024 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Face Amount | 500,000,000 |  | 500,000,000
Unamortized Debt Issuance Expense | 7,224,000 |  | 7,455,000
Senior Notes, Noncurrent | 492,776,000 |  | 492,545,000
5.625% Senior Notes Due 2025 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Face Amount | 500,000,000 |  | 500,000,000
Unamortized Debt Issuance Expense | 8,298,000 |  | 8,524,000
Senior Notes, Noncurrent | 491,702,000 |  | $ 491,476,000
Senior Notes [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Covenant Compliance, Dividends Excluded From Computation | 6,500,000 |  |
Debt Instrument, Repurchased Face Amount | 46,300,000 |  |
Debt Instrument, Repurchased Settlement Amount | 29,900,000 |  |
Early Repayment of Senior Debt, Accrued | 10,000,000 |  |
Gain (Loss) on Extinguishment of Debt | 15,722,000 |  |
Debt Instrument, Repurchase Discount | 16,400,000 |  |
Amortization of Debt Issuance Costs Related to Repurchase of Debt Instrument | $ 700,000 |  |
Senior Notes [Member] | 6.50% Senior Notes Due 2021 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 6.50% |  |
Senior Notes [Member] | 6.125% Senior Notes Due 2022 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 6.125% |  |
Senior Notes [Member] | 6.50% Senior Notes Due 2023 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 6.50% |  |
Senior Notes [Member] | 5% Senior Notes Due 2024 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 5.00% |  |
Senior Notes [Member] | 5.625% Senior Notes Due 2025 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 5.625% |  |

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- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399 + Details
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- Definition Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 50 -Section 40 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=49170532&loc=d3e12317-112629 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 50 -Section 40 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=49170532&loc=d3e12355-112629 + Details
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- Definition Carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion. Senior note holders are paid off in full before any payments are made to junior note holders. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -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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- Definition The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.17) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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