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Condensed Consolidating Financial Information (Narrative) (Details) - USD ($) | Sep. 30, 2016 | Apr. 21, 2015 | Aug. 18, 2014
--- | --- | --- | ---
Senior Notes |  |  |
Condensed Financial Statements, Captions [Line Items] |  |  |
Debt instrument, amount |  |  | $ 600,000,000
Stated interest rate, percent |  |  | 7.75%
Guarantors |  |  |
Condensed Financial Statements, Captions [Line Items] |  |  |
Ownership percentage by parent | 100.00% |  |
Notes Due 2023 | Senior Notes |  |  |
Condensed Financial Statements, Captions [Line Items] |  |  |
Debt instrument, amount |  | $ 350,000,000.0 |
Stated interest rate, percent |  | 6.625% |

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