Description of Business (Details) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)
Entity Number of Employees	10,000			10,000
HVCC [Member]
Discontinued Operation, Gain (Loss) from Disposal of Discontinued Operation, before Income Tax	$ (1)	$ (3)	$ 0	$ (4)	$ (7)

Amount before tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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