v2.4.0.6

Long-Term Debt (Senior Notes Due 2016) (Details) (USD $) | 1 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | ---
Jan. 31, 2006 | Dec. 31, 2011 | Dec. 31, 2010 | Jan. 13, 2006
Debt Instrument [Line Items] |  |  |  |
Maturity |  | 2016 |  |
6 5/8% Senior Notes Due 2016 [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Face amount |  |  |  | $ 250,000,000
Stated interest rate |  | 6.625% | 6.625% | 6.625%
Maturity | 2016 | 2016 |  |
Issue discount |  | 815,000 |  |
Minimum debt amount guaranteed by subsidiaries |  | $ 5,000,000 |  |

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