Employee Benefits - Estimated Future Benefit Payments (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014
U.K. [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2015	$ 136
2016	145
2017	153
2018	161
2019	174
2020 - 2024	1,043
U.S. Pension Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2015	155
2016	163
2017	171
2018	182
2019	180
2020 - 2024	932
Other [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2015	44
2016	46
2017	47
2018	48
2019	49
2020 - 2024	263
Other Postretirement Benefit Plan, Defined Benefit [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2015	6
2016	6
2017	6
2018	6
2019	6
2020 - 2024	$ 33

Amount of benefits expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year from a defined benefit plan.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (f)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

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Amount of benefits expected to be paid in the next fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the fifth fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the fourth fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the third fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the second fiscal year following the latest fiscal year from a defined benefit plan.

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