Retirement Benefits Plans - Fair Value of Pension Plan Assets (Details 11) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	$ 4,372	$ 3,855
United States pension plans percentage of worldwide pension assets	67.00%
United Kingdom pension plans percentage of worldwide pension assets	26.00%
United States pension plans' target allocation of United States equities	36.00%
United States pension plans' target allocation of non-United States equities	32.00%
United States pension plans' target allocation of real estate	7.00%
United States pension plans' target allocation of debt securities and other, including cash equivalents	25.00%
United Kingdom pension plans' target allocation of equities	57.00%
Quoted prices in active markets for identical assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	471	416
Other observable inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	3,801	3,398
Unobservable inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	100	41
Non-United States Equity and Global Equities [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	1,453	1,313
Non-United States Equity and Global Equities [Member] | Quoted prices in active markets for identical assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Non-United States Equity and Global Equities [Member] | Other observable inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	1,453	1,313
Non-United States Equity and Global Equities [Member] | Unobservable inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
United States Equity [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	1,153	978
United States Equity [Member] | Quoted prices in active markets for identical assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
United States Equity [Member] | Other observable inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	1,153	978
United States Equity [Member] | Unobservable inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Fixed Income [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	609	538
Fixed Income [Member] | Quoted prices in active markets for identical assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Fixed Income [Member] | Other observable inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	609	538
Fixed Income [Member] | Unobservable inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Long Duration Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	63	61
Long Duration Funds [Member] | Quoted prices in active markets for identical assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Long Duration Funds [Member] | Other observable inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	63	61
Long Duration Funds [Member] | Unobservable inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Exchange Traded Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	64	43
Exchange Traded Funds [Member] | Quoted prices in active markets for identical assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Exchange Traded Funds [Member] | Other observable inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	64	43
Exchange Traded Funds [Member] | Unobservable inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	274	331
Fixed Income Securities [Member] | Quoted prices in active markets for identical assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Fixed Income Securities [Member] | Other observable inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	274	331
Fixed Income Securities [Member] | Unobservable inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
United States treasuries [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	63	143
United States treasuries [Member] | Quoted prices in active markets for identical assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	63	143
United States treasuries [Member] | Other observable inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
United States treasuries [Member] | Unobservable inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Real Estate Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	220	124
Real Estate Securities [Member] | Quoted prices in active markets for identical assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	214	119
Real Estate Securities [Member] | Other observable inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Real Estate Securities [Member] | Unobservable inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	6	5
Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	141	104
Equity Securities [Member] | Quoted prices in active markets for identical assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	141	104
Equity Securities [Member] | Other observable inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Equity Securities [Member] | Unobservable inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	187	140
Cash Equivalents [Member] | Quoted prices in active markets for identical assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	6	7
Cash Equivalents [Member] | Other observable inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	181	133
Cash Equivalents [Member] | Unobservable inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Exchange Traded Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	47	40
Exchange Traded Funds [Member] | Quoted prices in active markets for identical assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	47	40
Exchange Traded Funds [Member] | Other observable inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Exchange Traded Funds [Member] | Unobservable inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Other Pension Plan Assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	98	40
Other Pension Plan Assets [Member] | Quoted prices in active markets for identical assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	3
Other Pension Plan Assets [Member] | Other observable inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	4	1
Other Pension Plan Assets [Member] | Unobservable inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	$ 94	$ 36