Fair Value Measurements Changes in Fair Value Level 3 (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Other Segments and Holding Company [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	$ 228	$ 154	$ 138
Purchases	100	0
Transfers (out) in	(47)	3
Realized and unrealized losses	21	(97)
Distribution-in-kind	0
Investment Segment [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	55	75	287
Realized and unrealized losses	(20)	(100)
Gross proceeds	0	(2)
Distribution-in-kind	0	(110)
Fair Value, Inputs, Level 3 [Member] \| Recurring measurement [Member] \| Railcar and Food Packaging [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	21	21	21
Realized/unrealized (losses) gains, net	0	1
Purchases and settlements, net	0	(1)
Non-U.S. Plans \| Fair Value, Inputs, Level 3 [Member] \| Recurring measurement [Member] \| Automotive Segment [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	40	41	44
Gross proceeds	(4)	(5)
Foreign currency exchange rate movements	(4)	(6)
Realized/unrealized (losses) gains, net	1	2
Purchases and settlements, net	6	6
United States Plans \| Fair Value, Inputs, Level 3 [Member] \| Recurring measurement [Member] \| Automotive Segment [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	86	91	$ 85
Gross proceeds	0	(47)
Realized/unrealized (losses) gains, net	(5)	6
Purchases and settlements, net	$ 0	$ 47

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- Definition

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Foreign Exchange Movements

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No definition available.

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- Definition

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Net Realized And Unrealized Gains Losses

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No definition available.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
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-Section 50
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Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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-Name Accounting Standards Codification
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Amount of purchases, (sales), issuances and (settlements) of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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-Section 50
-Paragraph 2
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Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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- Definition

Amount of transfer of financial instrument classified as an asset into level 3 of the fair value hierarchy.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(3)
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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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-SubTopic 10
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-Subparagraph (c)
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