For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Retirement Benefits (Narrative) (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended			9 Months Ended
	Oct. 28, 2016	Sep. 30, 2016	Sep. 30, 2015	Mar. 31, 2015	Sep. 30, 2016	Sep. 30, 2015
Defined Benefit Plan Disclosure [Line Items]
Contributions to U.S. non qualified and non-U.S. Pension Plan					$ 159
Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit credit		$ (2)	$ (1)	$ 125	(6)	$ 121
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit credit		$ 13	$ (21)		52	$ (83)
Expected contribution during remainder of 2016					$ 58
Unites States \| Equity Funds
Defined Benefit Plan Disclosure [Line Items]
Target asset allocation U.S. Plan					64.00%
Actual asset allocation percentage of equity		63.00%			63.00%
Unites States \| Fixed Income Funds
Defined Benefit Plan Disclosure [Line Items]
Target asset allocation U.S. Plan					36.00%
Actual asset allocation percentage of equity		37.00%			37.00%
United Kingdom \| Equity Funds
Defined Benefit Plan Disclosure [Line Items]
Target asset allocation U.S. Plan					48.00%
Actual asset allocation percentage of equity		46.00%			46.00%
United Kingdom \| Fixed Income Funds
Defined Benefit Plan Disclosure [Line Items]
Target asset allocation U.S. Plan					52.00%
Actual asset allocation percentage of equity		54.00%			54.00%
United Kingdom \| Geographic Concentration Risk \| Non-U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Concentration risk percentage					83.00%
Subsequent Event
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution, percent of employees' gross pay (up to)	4.00%
Maximum annual contributions per employee, percent	7.00%