Face (par) amount of debt instrument at time of issuance.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

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Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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.

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- Definition

Amount of increase (decrease) of the credit facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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Debt - Narrative (Details) - USD ($)	3 Months Ended
Debt - Narrative (Details) - USD ($)	Mar. 31, 2017	Apr. 28, 2017	Jan. 31, 2017	Dec. 31, 2016
Line of Credit [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Increase in credit facilities during period	$ 182,000,000
Secured Debt [Member] \| Securitization Notes Payable [Member]
Debt Instrument [Line Items]
Debt instrument, face amount	4,003,000,000
Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, face amount	$ 31,549,000,000			$ 29,008,000,000
Parent Company [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, face amount			$ 2,500,000,000.0
Parent Company [Member] \| Senior Notes [Member] \| 3.45% Senior Notes Due January 2022 [Member]
Debt Instrument [Line Items]
Debt instrument, face amount			1,250,000,000
Interest rate (percent)	3.45%
Parent Company [Member] \| Senior Notes [Member] \| 3.45% Senior Notes Due January 2027 [Member]
Debt Instrument [Line Items]
Debt instrument, face amount			750,000,000
Interest rate (percent)	4.35%
Parent Company [Member] \| Senior Notes [Member] \| Floating Rate Senior Notes Due 2022 [Member]
Debt Instrument [Line Items]
Debt instrument, face amount			$ 500,000,000
Subsequent Event [Member] \| Parent Company [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, face amount		$ 3,000,000,000
Subsequent Event [Member] \| Parent Company [Member] \| Senior Notes [Member] \| 2.65% Senior Notes Due April 2020 [Member]
Debt Instrument [Line Items]
Debt instrument, face amount		$ 1,000,000,000
Interest rate (percent)		2.65%
Subsequent Event [Member] \| Parent Company [Member] \| Senior Notes [Member] \| 3.95% Senior Notes Due April 2024 [Member]
Debt Instrument [Line Items]
Debt instrument, face amount		$ 1,250,000,000.00
Interest rate (percent)		3.95%
Subsequent Event [Member] \| Parent Company [Member] \| Senior Notes [Member] \| Floating Rate Senior Notes Due 2020 [Member]
Debt Instrument [Line Items]
Debt instrument, face amount		$ 750,000,000