Changes In Debt Obligations [Roll Forward]

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- Definition

Changes In Short-Term Debt Obligations [Roll Forward]

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Changes in Long-Term Debt Obligations [Roll Forward]

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Payments (Accretions) And Other Of Long-Term And Short-Term Debt

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Payments (Accretions) And Other of Long-term Debt

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[Line Items] for Schedule of Debt [Table]

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The average effective interest rate during the reporting period.

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

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Represents the aggregate of total long-term debt, including current maturities and short-term debt.

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No definition available.

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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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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

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The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

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The net cash inflow or outflow for borrowing having initial term of repayment within one year or the normal operating cycle, if longer.

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The cash inflow from a borrowing having initial term of repayment within one year or the normal operating cycle, if longer.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Debt Obligations (Changes in Debt Obligations) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Apr. 30, 2017	Jun. 30, 2016	May 31, 2016	May 31, 2014	Jun. 30, 2013	Jan. 31, 2010
Changes In Short-Term Debt Obligations [Roll Forward]
Short-term debt - commercial paper beginning balance	$ 1,078,000,000
Additions	4,096,000,000
Payments, Accretion and Other	(4,299,000,000)
Short-term debt - commercial paper ending balance	875,000,000
Changes in Long-Term Debt Obligations [Roll Forward]
Long-term debt obligations at beginning of period	3,129,000,000
Additions	0
Payments, Accretion and Other	(173,000,000)
Long-term debt obligations at end of period	2,956,000,000
Changes In Debt Obligations [Roll Forward]
Total debt obligations at beginning of period	4,207,000,000
Additions	4,096,000,000
Payments, Accretion and Other	(4,472,000,000)
Total debt obligations at end of period	$ 3,831,000,000
Senior Notes \| 5.55% senior unsecured notes due January 15, 2020
Schedule of Debt [Line Items]
Stated rate	5.55%						5.55%
Changes in Long-Term Debt Obligations [Roll Forward]
Long-term debt obligations at beginning of period	$ 599,000,000
Additions	0
Payments, Accretion and Other	0
Long-term debt obligations at end of period	$ 599,000,000
Senior Notes \| 3.875% senior unsecured notes due June 7, 2021
Schedule of Debt [Line Items]
Stated rate	3.875%					3.875%
Changes in Long-Term Debt Obligations [Roll Forward]
Long-term debt obligations at beginning of period	$ 716,000,000
Additions	0
Payments, Accretion and Other	(30,000,000)
Long-term debt obligations at end of period	$ 686,000,000
Senior Notes \| 4.25% senior unsecured notes due June 1, 2024
Schedule of Debt [Line Items]
Stated rate	4.25%				4.25%
Changes in Long-Term Debt Obligations [Roll Forward]
Long-term debt obligations at beginning of period	$ 496,000,000
Additions	0
Payments, Accretion and Other	1,000,000
Long-term debt obligations at end of period	$ 497,000,000
Senior Notes \| 1.75% senior unsecured notes due May 19, 2023
Schedule of Debt [Line Items]
Stated rate	1.75%			1.75%
Changes in Long-Term Debt Obligations [Roll Forward]
Long-term debt obligations at beginning of period	$ 712,000,000
Additions	0
Payments, Accretion and Other	(30,000,000)
Long-term debt obligations at end of period	$ 682,000,000
Senior Notes \| 3.85% senior unsecured notes due June 30, 2026
Schedule of Debt [Line Items]
Stated rate	3.85%		3.85%
Changes in Long-Term Debt Obligations [Roll Forward]
Long-term debt obligations at beginning of period	$ 496,000,000
Additions	0
Payments, Accretion and Other	0
Long-term debt obligations at end of period	496,000,000
Revolving Credit Facility \| $1 billion revolving credit commitment due April 25, 2022 (average interest rate of 2.74% for the period January 1, 2018 through December 31, 2018)
Schedule of Debt [Line Items]
Facility borrowing capacity	$ 1,000,000,000	$ 1,000,000,000
Interest rate	2.74%
Changes in Long-Term Debt Obligations [Roll Forward]
Long-term debt obligations at beginning of period	$ 110,000,000
Additions	0
Payments, Accretion and Other	(114,000,000)
Long-term debt obligations at end of period	(4,000,000)
Commercial paper
Changes In Short-Term Debt Obligations [Roll Forward]
Short-term debt - commercial paper beginning balance	480,000,000
Additions	4,096,000,000
Payments, Accretion and Other	(4,301,000,000)
Short-term debt - commercial paper ending balance	275,000,000
Senior unsecured floating rate notes due March 22, 2019
Changes In Short-Term Debt Obligations [Roll Forward]
Short-term debt - commercial paper beginning balance	498,000,000
Additions	0
Payments, Accretion and Other	2,000,000
Short-term debt - commercial paper ending balance	500,000,000
$400 million senior unsecured term loan facility due November 25, 2019 (average interest rate of 3.48% for the period January 1, 2018 through December 31, 2018)(2)
Schedule of Debt [Line Items]
Facility borrowing capacity	$ 400,000,000
Interest rate	3.48%
Changes In Short-Term Debt Obligations [Roll Forward]
Short-term debt - commercial paper beginning balance	$ 100,000,000
Additions	0
Payments, Accretion and Other	0
Short-term debt - commercial paper ending balance	$ 100,000,000