Commitments and Contingencies (Details 1) $ in Millions	Dec. 31, 2014 USD ($)
Future minimum rental commitments under all non-cancellable operating lease agreements
2014	$ 546
Thereafter	2,206
Contractual Obligation	4,953
Gross rental commitments
Future minimum rental commitments under all non-cancellable operating lease agreements
2014	128
2015	115
2016	106
2017	91
2018	84
Thereafter	657
Contractual Obligation	1,181
Rentals from subleases
Future minimum rental commitments under all non-cancellable operating lease agreements
2014	(13)
2015	(13)
2016	(12)
2017	(7)
2018	(5)
Thereafter	(10)
Contractual Obligation	(60)
Net rental commitments
Future minimum rental commitments under all non-cancellable operating lease agreements
2014	115
2015	102
2016	94
2017	84
2018	79
Thereafter	647
Contractual Obligation	$ 1,121

- Definition

Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of contractual obligation maturing after the fifth fiscal year following the latest fiscal year.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of contractual obligation maturing in the fifth fiscal year following the latest fiscal year.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of contractual obligation maturing in the fourth fiscal year following the latest fiscal year.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of contractual obligation maturing in the next fiscal year following the latest fiscal year.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of contractual obligation maturing in the second fiscal year following the latest fiscal year.

+ References

No definition available.

+ Details

Name:	us-gaap_ContractualObligationDueInSecondYear
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of contractual obligation maturing in the third fiscal year following the latest fiscal year.

+ References

No definition available.

+ Details

Name:	us-gaap_ContractualObligationDueInThirdYear
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

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Namespace Prefix:
Data Type:	na
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- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
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Period Type: