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

+ Details

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Balance Type:	credit
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.

+ Details

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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

+ Details

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Period Type:	instant

- Details

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- Details

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Condensed Consolidating Financial Statements - Narrative (Details) - USD ($)	Dec. 31, 2017	Sep. 22, 2016	Aug. 31, 2015	Aug. 18, 2015	May 26, 2015
Debt Instrument [Line Items]
Ownership interest of subsidiary (as a percent)	100.00%
Senior Notes
Debt Instrument [Line Items]
Debt face amount			$ 2,000,000,000.0	$ 2,000,000,000.0
Senior Notes \| 2.95% Senior Notes, due 2027
Debt Instrument [Line Items]
Debt face amount		$ 500,000,000
Interest rate (as a percent)	2.95%	2.95%
Senior Notes \| 4.0% Senior Notes, due 2025
Debt Instrument [Line Items]
Debt face amount					$ 700,000,000
Interest rate (as a percent)	4.00%				4.00%
Senior Notes \| 2.5% Senior Notes, due 2018
Debt Instrument [Line Items]
Debt face amount				$ 400,000,000
Interest rate (as a percent)	2.50%			2.50%
Senior Notes \| 3.3% Senior Notes, due 2020
Debt Instrument [Line Items]
Debt face amount				$ 700,000,000
Interest rate (as a percent)	3.30%			3.30%
Senior Notes \| 4.4% Senior Notes, due 2026
Debt Instrument [Line Items]
Debt face amount				$ 900,000,000
Interest rate (as a percent)	4.40%			4.40%