Summary Of Significant Accounting Policies (Assets And Liabilities Measured At Fair Value On A Recurring Basis) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total net liability	$ (1,127,850)
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total net liability	(994,311)
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total net liability	(133,539)	[1]
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total net liability
Foreign Currency Forwards [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	146
Foreign Currency Forwards [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets
Foreign Currency Forwards [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	146	[1]
Foreign Currency Forwards [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets
Oil Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	5,800
Oil Contracts [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets
Oil Contracts [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	5,800	[1]
Oil Contracts [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets
Oil Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities	15,777
Oil Contracts [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities
Oil Contracts [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities	15,777	[1]
Oil Contracts [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities
Fair Value Of Long Term Debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities	1,117,498	[2]
Fair Value Of Long Term Debt [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities	994,311	[2]
Fair Value Of Long Term Debt [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities	123,187	[1],[2]
Fair Value Of Long Term Debt [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities		[2]
Interest Rate Swaps [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities	521	[2]
Interest Rate Swaps [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities		[2]
Interest Rate Swaps [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities	521	[1],[2]
Interest Rate Swaps [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities		[2]

[1] Unless otherwise indicated, the fair value of our Level 2 derivative instruments reflects our best estimate and is based upon exchange or over-the-counter quotations whenever they are available. Quoted valuations may not be available due to location differences or terms that extend beyond the period for which quotations are available. Where quotes are not available, we utilize other valuation techniques or models to estimate market values. These modeling techniques require us to make estimations of future prices, price correlation and market volatility and liquidity based on market data. Our actual results may differ from our estimates, and these differences could be positive or negative.

[2] See Note 7 for additional information regarding our long-term debt. The fair value of our long-term debt at December 31, 2012 and 2011 is as follows: 20122011Carrying ValueFair ValueCarrying ValueFair ValueTerm Loans (mature July 2015) (a)$ 367,181$ 368,295$ 279,750$ 279,750Revolving Credit Facility (matures July 2015) (a) 100,000 100,000 - -2025 Notes (mature December 2025) (b) 3,487 3,487 300,000 300,5432032 Notes (mature March 2032) (c) 200,000 239,320 - -Senior Unsecured Notes (mature January 2016) 274,960 283,209 474,960 501,083MARAD Debt (matures February 2027) (d) 105,288 123,187 110,166 124,488Total debt$ 1,050,916$ 1,117,498$ 1,164,876$ 1,205,864(a) In February 2013, we repaid $293.9 million of our Term Loans and $24.5 million under our Revolving Credit Facility with the after-tax proceeds from the sale of ERT. (b) Carrying value excludes the related unamortized debt discount of $9.6 million at December 31, 2011. This remaining amount was repurchased by us in February 2013. (c) Carrying value excludes the related unamortized debt discount of $31.7 million at December 31, 2012. (d ) The estimated fair value of all debt, other than the MARAD debt, was determined using Level 1 inputs using the market approach. The fair value of the MARAD debt was determined using a third party evaluation of the remaining average life and outstanding principal balance of the MARAD indebtedness as compared to other governmental obligations in the marketplace with similar terms. The fair value of the MARAD Debt was estimated using Level 2 fair value inputs using the market approach.