Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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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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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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Number of reporting units tested for impairment of goodwill. A reporting unit is an operating segment or one level below an operating segment.

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Fair Value of Financial Instruments - Fair Value of Long Term Debt (Details) $ in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2019 USD ($) reporting_unit	Jun. 30, 2018 USD ($)	Dec. 31, 2018 USD ($)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Number of reporting units \| reporting_unit				9
Goodwill impairment charge	$ 0	$ 60	$ 0	$ 60	$ 0
Carrying Amount	5,588			5,588		$ 5,413
Term loans and senior notes \| Carrying Amount \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value of long term debt	5,247			5,247		5,307
Term loans and senior notes \| Fair Value \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value of long term debt	5,035			5,035		5,218
Other Debt
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Carrying Amount	$ 91			$ 91		$ 106
Ride Performance
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Number of reporting units \| reporting_unit				2
Goodwill impairment charge		$ 60		$ 60