Indebtedness - Summary of Other Non-Recourse Debt (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Non-recourse debt	$ 4,945	$ 5,286
Unamortized debt issuance costs, premium and discount	7	10
Participating interest financing(1)
Debt Instrument [Line Items]
Non-recourse debt	4,045	4,284
Trust 2019-2
Debt Instrument [Line Items]
Collateral Amount	306
Non-recourse debt	297	333
Trust 2019-1
Debt Instrument [Line Items]
Collateral Amount	286
Non-recourse debt	269	302
Trust 2018-3
Debt Instrument [Line Items]
Collateral Amount	209
Non-recourse debt	190	209
Trust 2018-2
Debt Instrument [Line Items]
Collateral Amount	157
Non-recourse debt	137	148
Other
Debt Instrument [Line Items]
Non-recourse debt	4,938	$ 5,276
Nonrecourse debt–legacy assets \| Participating interest financing(1)
Debt Instrument [Line Items]
Collateral Amount	$ 0

Amount of assets pledged to secure a debt instrument.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

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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.

+ References

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Amount of unamortized debt discount (premium) and debt issuance costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6031897-161870

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28555-108399

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- Definition

Amount of debt for which creditor does not have general recourse to the debtor but rather has recourse only to the property used for collateral in the transaction or other specific property.

+ References

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