Debt (Schedule Of Outstanding Debt) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Debt Instrument [Line Items]
Long-term debt, current and noncurrent	$ 2,928	$ 3,034
Current portion of long-term debt	260	8
Long-term Debt and Capital Lease Obligations	2,668	3,026
Senior Debt Obligations Due 2012 [Member]
Debt Instrument [Line Items]
Long-term Debt and Capital Lease Obligations	250	253
Debt instrument, interest rate, stated percentage	6.25%
Debt instrument, interest rate, effective percentage	5.10%
Senior Debt Obligations Due 2013 [Member]
Debt Instrument [Line Items]
Long-term Debt and Capital Lease Obligations	251	250
Debt instrument, interest rate, stated percentage	4.85%
Senior Debt Obligations Due 2033 [Member]
Debt Instrument [Line Items]
Long-term Debt and Capital Lease Obligations	296	296
Debt instrument, interest rate, stated percentage	5.875%
Senior Debt Obligations Due 2014 [Member]
Debt Instrument [Line Items]
Long-term Debt and Capital Lease Obligations	326	648
Debt instrument, interest rate, stated percentage	5.375%
Senior Debt Obligations Due 2015 [Member]
Debt Instrument [Line Items]
Long-term Debt and Capital Lease Obligations	479	747
Debt instrument, interest rate, stated percentage	5.75%
Senior Debt Obligations Due 2019 [Member]
Debt Instrument [Line Items]
Long-term Debt and Capital Lease Obligations	398	398
Debt instrument, interest rate, stated percentage	9.25%
Senior Debt Obligations Due 2021 [Member]
Debt Instrument [Line Items]
Long-term Debt and Capital Lease Obligations	496	0
Debt instrument, interest rate, stated percentage	4.80%
Mortgage Due 2035 [Member]
Debt Instrument [Line Items]
Long-term Debt and Capital Lease Obligations	431	439
Debt instrument, interest rate, stated percentage	5.70%
Other [Member]
Debt Instrument [Line Items]
Long-term Debt and Capital Lease Obligations	$ 1	$ 3