Employee Benefit Plans, Fair Value of Assets Qualified Plans (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011 method		Dec. 31, 2010
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	$ 1,487		$ 1,362
Employee Benefit Plans (Textual)
Percentage of equity securities in target allocations for plan assets	70.00%
Percentage of fixed income investments in target allocations for plan assets	30.00%
Methods of expected returns on plan assets by class	3
Fair Value, Inputs, Level 1 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	1,223		1,113
Fair Value, Inputs, Level 2 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	264		249
Fair Value, Inputs, Level 3 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	0		0
Common Stock [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	5		5
Common Stock [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	5		5
Common Stock [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	0		0
Common Stock [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	0		0
Other US Companies [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	375	[1]	369	[1]
Other US Companies [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	375	[1]	369	[1]
Other US Companies [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	0	[1]	0	[1]
Other US Companies [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	0	[1]	0	[1]
International Companies [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	120		107
International Companies [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	120		107
International Companies [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	0		0
International Companies [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	0		0
Preferred Stock [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	2		1
Preferred Stock [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	2		1
Preferred Stock [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	0		0
Preferred Stock [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	0		0
International Growth [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	102		117
International Growth [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	102		117
International Growth [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	0		0
International Growth [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	0		0
Index Funds [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	63	[2]	64	[2]
Employee Benefit Plans (Textual)
Percentage of equity securities in target allocations for plan assets	60.00%
Percentage of fixed income investments in target allocations for plan assets	40.00%
Index Funds [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	63	[2]	64	[2]
Index Funds [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	0	[2]	0	[2]
Index Funds [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	0	[2]	0	[2]
Corporate Debt Instruments [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	246		274
Corporate Debt Instruments [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	246		274
Corporate Debt Instruments [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	0		0
Corporate Debt Instruments [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	0		0
US Treasury Securities [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	67		30
US Treasury Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	67		30
US Treasury Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	0		0
US Treasury Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	0		0
Mortgage-backed Securities [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	3		3
Mortgage-backed Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	3		3
Mortgage-backed Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	0		0
Mortgage-backed Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	0		0
Other Government Securities [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	81		93
Other Government Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	81		93
Other Government Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	0		0
Other Government Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	0		0
Common Collective Trusts [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	247		231
Common Collective Trusts [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	0		0
Common Collective Trusts [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	247		231
Common Collective Trusts [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	0		0
Insurance Contracts [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	17		18
Insurance Contracts [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	0		0
Insurance Contracts [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	17		18
Insurance Contracts [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	0		0
Interest and Dividends Receivable [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	5		5
Interest and Dividends Receivable [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	5		5
Interest and Dividends Receivable [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	0		0
Interest and Dividends Receivable [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	0		0
Cash and Cash Equivalents [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	154		45
Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	154		45
Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	0		0
Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	$ 0		$ 0

[1] Equity securities are held in a wide range of industrial sectors, including consumer goods, information technology, healthcare, industrials, and financial services.

[2] This class include primarily investments in approximately 60 percent equities and 40 percent bonds.