Goodwill and Net Intangible Assets (Amortizable Intangible Assets) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Gross Carrying Amount	$ 5,026	$ 4,782
Accumulated Amortization	1,250	910
Trademarks
Gross Carrying Amount	7	59
Accumulated Amortization	3	13
Trade Names
Gross Carrying Amount	280	0
Accumulated Amortization	2	0
Customer Relationships
Gross Carrying Amount	4,058	4,063
Accumulated Amortization	923	673
Management Contracts
Gross Carrying Amount	313	313
Accumulated Amortization	116	80
Research
Gross Carrying Amount	176	176
Accumulated Amortization	126	91
Other
Gross Carrying Amount	192	171
Accumulated Amortization	$ 80	$ 53

Sum of the gross carrying amounts before accumulated amortization as of the balance sheet date of all intangible assets having statutory or estimated useful lives. The aggregate gross carrying amount (including any previously recognized impairment charges) of a major finite-lived intangible asset class. A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 45

-Subparagraph a(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6905858&loc=d3e16323-109275

Name:	us-gaap_FiniteLivedIntangibleAssetsGross
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant