Claims, Lawsuits, and Other Contingencies - Guarantees and Indemnifications Narrative (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Loss Contingencies [Line Items]
Maximum potential funding under commitments	$ 103	$ 95
Discontinued Operations, Disposed of by Sale \| Tempo Business \| Property Lease Guarantee
Loss Contingencies [Line Items]
Maximum potential funding under commitments	85
Guarantor obligations, current carrying value	17
Discontinued Operations, Disposed of by Sale \| Tempo Business \| Performance Guarantee
Loss Contingencies [Line Items]
Maximum potential funding under commitments	188
Guarantor obligations, current carrying value	$ 1

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=115931803&loc=d3e12069-110248

+ Details

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

- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=115931803&loc=d3e12069-110248

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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- Details

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