Employee Benefit Plans, Fair Value of Assets Qualified Plans (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012 method		Dec. 31, 2011
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	$ 1,729		$ 1,487
Employee Benefit Plans (Textual)
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	1,035		892
Fair Value, Inputs, Level 2 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	694		595
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
Common Stock [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets			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
Common Stock [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets			0
Other US Companies [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	441	[1]	375	[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	441	[1]	375	[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	135		120
International Companies [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	135		120
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	3		2
Preferred Stock [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	2		2
Preferred Stock [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	1		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	127		102
International Growth [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	127		102
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	117	[2]	63	[2]
Index Funds [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	117	[2]	63	[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	290		246
Corporate Debt Instruments [Member] | Fair Value, Inputs, Level 1 [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 2 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	290		246
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	107		67
US Treasury Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	107		67
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
Other Government Securities [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	68		84
Other Government Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	3		0
Other Government Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Values of Qualified Pension Plan Assets
Fair value of qualified pension plan assets	65		84
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	294		247
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	294		247
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		17
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		17
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	125		154
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	98		153
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	27		1
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
Equity Securities [Member]
Fair Values of Qualified Pension Plan Assets
Defined benefit plan, actual plan asset allocations	60.00%
Employee Benefit Plans (Textual)
Percentage of equity securities in target allocations for plan assets	70.00%
Debt Securities [Member]
Fair Values of Qualified Pension Plan Assets
Defined benefit plan, actual plan asset allocations	40.00%
Employee Benefit Plans (Textual)
Percentage of equity securities in target allocations for plan assets	30.00%

[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 includes primarily investments in approximately 60 percent equities and 40 percent bonds.