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Long-Term Debt (Narrative) (Details) (USD $) | 6 Months Ended | 3 Months Ended | 6 Months Ended | 3 Months Ended |  |  | 6 Months Ended
--- | --- | --- | --- | --- | --- | --- | ---
Jun. 30, 2014 Senior Credit Agreement | Mar. 31, 2013 Senior Subordinated 8% Notes, Due December 1, 2015 | Jun. 30, 2014 Revolving Credit Facility | Mar. 31, 2013 Senior Subordinated 6.25% Notes | Jun. 30, 2014 Senior Subordinated 6.25% Notes | Jan. 31, 2013 Senior Subordinated 6.25% Notes | Jun. 30, 2014 London Interbank Offering Rate (LIBOR) Minimum Revolving Credit Facility | Jun. 30, 2014 London Interbank Offering Rate (LIBOR) Maximum Revolving Credit Facility
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Debt instrument, issuance date |  |  |  | Jan. 31, 2013 |  |  |  |
Debt instrument, issued value |  | $ 204,000,000 |  |  |  | $ 210,000,000 |  |
Senior Subordinated Notes, interest rate |  | 8.00% |  | 6.25% | 6.25% |  |  |
Debt instrument, maturity date |  |  |  | Feb. 01, 2021 |  |  |  |
Loss on extinguishment of debt |  | 7,166,000 |  |  |  |  |  |
Prepayment premium for extinguishment of debt |  | 3,702,000 |  |  |  |  |  |
Write-off deferred financing fees |  | 2,199,000 |  |  |  |  |  |
Write off of debt discount |  | 1,265,000 |  |  |  |  |  |
Placement and other fees |  |  |  | 3,755,000 |  |  |  |
Maximum borrowing capacity under the revolving credit facility | 200,000,000 |  |  |  |  |  |  |
Revolving credit facility, increase, additional borrowings | 250,000,000 |  |  |  |  |  |  |
Revolving credit facility termination date |  |  | Oct. 10, 2016 |  |  |  |  |
LIBOR floor, plus |  |  |  |  |  |  | 2.00% | 2.50%
Revolving credit facility, annual commitment fee |  |  | 0.375% |  |  |  |  |
Standby letters of credit | 21,856,000 |  |  |  |  |  |  |
Revolving credit facility, availability amount |  |  | $ 118,438,000 |  |  |  |  |
Fixed charge coverage ratio | 125.00% |  |  |  |  |  |  |

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