Acquisition of Businesses Purchase Price Allocation (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Business Acquisition [Line Items]
Goodwill	$ 1,240	$ 1,108
Ally FInancial [Member]
Business Acquisition [Line Items]
Business Acquisition, Purchase Price Allocation, Current Assets, Cash and Cash Equivalents	607
Restricted Cash	906
Business Combination, Acquired Receivables, Fair Value	15,144
Business Acquisition, Purchase Price Allocation, Other Noncurrent Assets	781
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Financial Liabilities	(12,833)
Business Acquisition, Purchase Price Allocation, Other Noncurrent Liabilities	(1,483)
Identifiable net assets acquired	3,122
Goodwill	132
Business Acquisition, Cost of Acquired Entity, Purchase Price	$ 3,254

Amount of restricted cash acquired at the acquisition date.

No definition available.

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- Definition

For receivables acquired in a business combination, excluding certain loans and debt securities acquired in a transfer (as defined), this element represents the fair value of the receivables acquired, by major class of receivable, such as loans, direct finance leases (as defined), and any other class of receivables.

+ References

+ Details

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- Definition

Amount of currency on hand as well as demand deposits with banks or financial institutions, acquired at the acquisition date. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

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- Definition

The amount of financial liabilities assumed (as defined) which have been recognized as of the acquisition date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 55

-Paragraph 37

-URI http://asc.fasb.org/extlink&oid=25498275&loc=d3e2207-128464

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financial Liability

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- Definition

Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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- Definition

Amount of other liabilities due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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- Definition

Amount of other assets expected to be realized or consumed after one year or the normal operating cycle, if longer, acquired at the acquisition date.

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- Definition

Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=14024403&loc=d3e13816-109267

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-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

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