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Fair Value Measurements (Narrative) (Details) $ in Thousands | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2015 USD ($) trail | Dec. 31, 2014 USD ($) | Jan. 31, 2013
Extinguishment of Debt [Line Items] |  |  |
Carrying value of outstanding debt | $ 209,282 | $ 209,911 |
Triangular distribution, number of trails | trail | 500,000 |  |
Senior Subordinated 6.25% Notes |  |  |
Extinguishment of Debt [Line Items] |  |  |
Carrying value of outstanding debt | $ 210,000 | $ 210,000 |
Senior Subordinated Notes, interest rate | 6.25% | 6.25% | 6.25%

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