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

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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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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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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average interest rate of debt outstanding.

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No definition available.

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- Definition

For an unclassified balance sheet, the carrying amount (net of accumulated amortization) as of the balance sheet date of capitalized costs associated with the issuance of debt instruments (for example, legal, accounting, underwriting, printing, and registration costs) that will be charged against earnings over the life of the debt instruments to which such costs pertain.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Period remaining on line of credit facility before it terminates, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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- Definition

Amount of increase (decrease) of the credit facility.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition

Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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-Number 210
-Section 02
-Paragraph 19, 20, 22
-Article 5

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Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

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Debt - Narrative (Details)	12 Months Ended
Debt - Narrative (Details)	Dec. 31, 2015 USD ($)	May. 31, 2015 CAD	Feb. 28, 2015 EUR (€)	Jan. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Debt Instrument [Line Items]
Total borrowing capacity	$ 5,200,000,000
Secured debt	30,689,000,000				$ 25,173,000,000
Unsecured debt	23,657,000,000				12,142,000,000
Face amount of debt	19,100,000,000				8,400,000,000
Revolving Credit Facilities [Member]
Debt Instrument [Line Items]
Secured debt	7,548,000,000				7,028,000,000
Unsecured debt	$ 2,759,000,000				2,974,000,000
Revolving Credit Facilities [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Expiration period	6 years
Senior Notes [Member]
Debt Instrument [Line Items]
Weighted average interest rate (percent)	3.37%
Unsecured debt	$ 19,100,000,000
Medium-term Notes [Member] \| Euro Medium Due February 2018 [Member]
Debt Instrument [Line Items]
Face amount of debt \| €			€ 650,000,000
Interest rate (percent)			0.85%
Unsecured Debt [Member]
Debt Instrument [Line Items]
Issuance costs	107,000,000				75,000,000
Secured Debt [Member]
Debt Instrument [Line Items]
Issuance costs	$ 76,000,000				60,000,000
Secured Debt [Member] \| Securitization Notes Payable [Member]
Debt Instrument [Line Items]
Weighted average interest rate (percent)	1.50%
Secured debt	$ 14,300,000,000
North America [Member]
Debt Instrument [Line Items]
Secured debt	23,151,000,000				15,422,000,000
Unsecured debt	17,731,000,000				7,777,000,000
North America [Member] \| Revolving Credit Facilities [Member]
Debt Instrument [Line Items]
Secured debt	3,246,000,000				1,701,000,000
Unsecured debt	$ 0				0
North America [Member] \| Secured Debt [Member]
Debt Instrument [Line Items]
Weighted average interest rate (percent)	1.63%
International [Member]
Debt Instrument [Line Items]
Secured debt	$ 7,538,000,000				9,751,000,000
Unsecured debt	5,926,000,000				4,365,000,000
International [Member] \| Revolving Credit Facilities [Member]
Debt Instrument [Line Items]
Secured debt	4,302,000,000				5,327,000,000
Unsecured debt	$ 2,759,000,000				2,974,000,000
International [Member] \| Line of Credit [Member]
Debt Instrument [Line Items]
Weighted average interest rate (percent)	8.72%
Increase in unsecured committed credit facilities	$ 334,000,000
Debt instrument term	5 years
International [Member] \| Secured Debt [Member]
Debt Instrument [Line Items]
Weighted average interest rate (percent)	3.10%
Parent Company [Member]
Debt Instrument [Line Items]
Secured debt	$ 0				0
Unsecured debt	17,087,000,000				$ 7,435,000,000
Parent Company [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Unsecured debt	$ 17,200,000,000
Face amount of debt				$ 9,700,000,000.0
Parent Company [Member] \| Senior Notes [Member] \| Floating Rate Senior Notes [Member]
Debt Instrument [Line Items]
Face amount of debt				800,000,000
Parent Company [Member] \| Senior Notes [Member] \| Fixed Rate Senior Notes [Member]
Debt Instrument [Line Items]
Face amount of debt				$ 8,900,000,000.0
Interest rate (percent)		3.38%
Parent Company [Member] \| Senior Notes [Member] \| Notes Due May 2020 [Member]
Debt Instrument [Line Items]
Face amount of debt \| CAD		CAD 500,000,000
Interest rate (percent)		3.08%