v2.3.0.15

Debt (Narrative) (Details) (USD $)	3 Months Ended	9 Months Ended			9 Months Ended											9 Months Ended	0 Months Ended	9 Months Ended	0 Months Ended	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2011	Sep. 30, 2011 4.70% Senior Notes Due 2021 [Member]	Sep. 30, 2011 4.70% Senior Notes Due 2021 [Member] Senior Notes [Member]	Sep. 30, 2011 8.50% Senior Notes Due 2019 [Member]	Sep. 30, 2011 8.50% Senior Notes Due 2019 [Member] Acquired Debt [Member]	Sep. 30, 2011 6.875% Senior Notes due 2020 [Member]	Sep. 30, 2011 6.875% Senior Notes due 2020 [Member] Acquired Debt [Member]	Sep. 30, 2011 7.875% Senior Notes Due 2040 [Member]	Sep. 30, 2011 7.875% Senior Notes Due 2040 [Member] Acquired Debt [Member]	Sep. 30, 2011 4.33% MARAD Bonds Due 2016 [Member]	Sep. 30, 2011 Unsecured 4.70% Senior Notes Due 2021 [Member] Senior Notes [Member]	Sep. 30, 2011 Unsecured 3.25% Senior Notes Due 2016 [Member] Senior Notes [Member]	Sep. 30, 2011 MARAD Bonds Due 2016 [Member] Acquired Debt [Member]	Sep. 30, 2011 Senior Notes [Member]	Sep. 30, 2011 Acquired Debt [Member]	Apr. 26, 2011 Commercial Paper Program [Member]	Sep. 30, 2011 Commercial Paper Program [Member]	May 31, 2011 Five-Year Credit Facility [Member]	Sep. 30, 2011 Five-Year Credit Facility [Member]	Sep. 30, 2011 364-Day Credit Facility [Member]	Sep. 30, 2011 Bridge Term Facility [Member]
Debt Instrument [Line Items]
Debt instrument issuance date													March 17, 2011					April 26, 2011		May 12, 2011	May 12, 2011	February 6, 2011
Aggregate amount of unsecured debt instrument				$ 1,500,000,000									$ 1,000,000,000					$ 1,000,000,000		$ 1,700,000,000		$ 2,800,000,000
Unsecured debt instrument issued						500,000,000		900,000,000		300,000,000				151,500,000		181,000,000	700,000,000	175,000,000	1,450,000,000	700,000,000	450,000,000
Discount to senior notes												29,600,000	7,600,000
Debt instrument interest rate stated percentage			4.70%		8.50%		6.875%		7.875%		4.33%	4.70%	3.25%
Aggregate redemption price of notes															100.00%
Maximum days of maturity of notes																		364			364
Debt instrument maturity term, years																				5
Debt instrument maturity date																					May 01, 2012
Percentage of LIBOR plus margin rate interest																				1.50%	1.50%
Undrawn facility fee																				0.20%	0.10%
Total facility fee commitment	1,450,000,000	1,450,000,000																			450,000,000
Maximum percentage of debt to total capitalization ratio																				50.00%	50.00%
Maximum amount of right to increase the commitment																					550,000,000
Term loan maturity date																					May 11, 2013
Percentage of fee of term loan																					1.00%
Debt Instrument Maturity Period			2021		2019		2020		2040		2016	2021	2016
Net unamortized premiums	355,800,000	355,800,000
Interest expense totaled	30,800,000	54,500,000
Net of amount capitalized	$ 27,100,000	$ 63,500,000

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Maximum Percentage Of Debt To Total Capitalization Ratio

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Net Of Amount Capitalized

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Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date before deducting unamortized discount or premiums (if any). May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer.

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Interest rate stated in the contractual debt agreement.

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Date when the debt instrument was issued, which may be presented in a variety of ways (year, month and year, day, month and year, quarter, etc.).

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Date when the debt instrument is scheduled to be fully repaid, which may be presented in a variety of ways (year, month and year, day, month and year, quarter, etc.).

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Description of the maturity date of the debt instrument including whether the debt matures serially and, if so, a brief description of the serial maturities.

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

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The fair value of notes issued in noncash investing and financing activities.

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Reflects the cumulative amount of fees paid by borrowers which have not yet been taken into income and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield.

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