Long-Term Debt (Details) (USD $)	3 Months Ended	12 Months Ended
Dec. 31, 2011	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Debt Instrument [Line Items]
Interest Expense		$ 248,344,000	$ 205,032,000	$ 31,419,000
Gains (Losses) on Extinguishment of Debt		16,090,000	0	0
Payments of Merger Related Costs, Financing Activities	14,907,000
Debt	3,133,993,000	3,133,993,000	3,145,365,000
Less amounts due in one year	(11,759,000)	(11,759,000)	(16,629,000)
Long-Term Debt	3,122,234,000	3,122,234,000	3,128,736,000
Senior Notes Due April 2017 at 8.00%
Debt Instrument [Line Items]
Debt	1,500,000,000	1,500,000,000	1,500,000,000
Interest rate stated percentage	8.00%	8.00%
Debt Instrument, Face Amount	1,500,000,000	1,500,000,000
Senior notes due April 2020 at 8.25%
Debt Instrument [Line Items]
Debt	1,250,000,000	1,250,000,000	1,250,000,000
Interest rate stated percentage	8.25%	8.25%
Debt Instrument, Face Amount	1,250,000,000	1,250,000,000
Senior notes due March 2021 at 6.375%
Debt Instrument [Line Items]
Debt	250,000,000	250,000,000	0
Interest rate stated percentage	6.375%	6.375%
Debt Instrument, Face Amount	250,000,000	250,000,000
Secured notes due March 2012 at 7.875%
Debt Instrument [Line Items]
Redemption Premium		15,785,000
Interest Expense		2,188,000
Subsequent Event, Total Debt Redemption Cost	267,973,000	267,973,000
Gains (Losses) on Extinguishment of Debt		16,090,000
Debt	0	0	249,758,000
Interest rate stated percentage	7.875%	7.875%
Debt Instrument, Unamortized Discount	0	0	242,000
Debt Instrument, Face Amount	0	0	250,000,000
Baltimore Port Facility revenue bonds in series due September 2025 at 5.75%
Debt Instrument [Line Items]
Debt	102,865,000	102,865,000	102,865,000
Interest rate stated percentage	5.75%	5.75%
Advance royalty commitments
Debt Instrument [Line Items]
Debt	31,053,000	31,053,000	32,211,000
Interest rate stated percentage	6.78%	6.78%	7.56%
Note due through December 2012 at 6.10%
Debt Instrument [Line Items]
Debt	0	0	10,438,000
Interest rate stated percentage	6.10%	6.10%
Other long-term notes maturing at various dates through 2031
Debt Instrument [Line Items]
Debt	$ 75,000	$ 75,000	$ 93,000

Subsequent Event, Total Debt Redemption Cost.

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The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.

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Interest rate stated in the contractual debt agreement.

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The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

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Amount represents the difference between the fair value of the payments made and the carrying amount of the debt at the time of its extinguishment.

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The cost of borrowed funds accounted for as interest that was charged against earnings during the period.

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Total of the portions of the carrying amounts as of the balance sheet date of long-term debt, which may include notes payable, bonds payable, debentures, mortgage loans, and commercial paper, which are scheduled to be repaid within one year or the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

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Sum of the carrying values as of the balance sheet date of all long-term debt, which is debt initially having maturities due after one year from the balance sheet date or beyond the operating cycle, if longer, but excluding the portions thereof scheduled to be repaid within one year (current maturities) or the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

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The cash outflow for financing costs associated with business combinations.

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The excess of the (1) fair value of consideration transferred to the holders of a security in excess of (2) the carrying amount of the security reported on the registrant's balance sheet, which will be deducted from net earnings to derive net earnings available to common shareholders. This amount is generally an adjustment considered in the computation of earnings per share.

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