Condensed Consolidating Financial Information (Narrative) (Details) - USD ($) |
Mar. 31, 2018 |
Oct. 11, 2017 |
Dec. 21, 2016 |
Oct. 14, 2016 |
Apr. 21, 2015 |
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| 6.625% Senior Notes due 2023 | Senior notes | |||||
| Condensed Financial Statements, Captions [Line Items] | |||||
| Debt instrument, amount | $ 350,000,000.0 | ||||
| 6.000% Senior Notes due 2024 | Senior notes | |||||
| Condensed Financial Statements, Captions [Line Items] | |||||
| Debt instrument, amount | $ 650,000,000.0 | ||||
| 6.375% Senior Notes due 2025 | Senior notes | |||||
| Condensed Financial Statements, Captions [Line Items] | |||||
| Debt instrument, amount | $ 600,000,000.0 | ||||
| 6.375% Senior Notes Due 2026 | Senior notes | |||||
| Condensed Financial Statements, Captions [Line Items] | |||||
| Debt instrument, amount | $ 450,000,000.0 | ||||
| Guarantors | |||||
| Condensed Financial Statements, Captions [Line Items] | |||||
| Ownership percentage by parent | 100.00% |
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Face (par) amount of debt instrument at time of issuance. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The parent entity's interest in net assets of the subsidiary, expressed as a percentage. No definition available.
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