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

Face (par) amount of the original debt instrument that was repurchased.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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.

+ References

No definition available.

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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=49170532&loc=d3e12317-112629

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=49170532&loc=d3e12355-112629

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- Details

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- Details

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Long-Term Debt and Short-Term Borrowings - Narrative (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended
	Oct. 31, 2017	Dec. 31, 2017	Jun. 30, 2017
Estimated Financial Impact
Debt instrument
Debt repurchases	$ 305
Loss on early debt extinguishment		$ 95
Fixed rate medium term note due 2023 \| Estimated Financial Impact
Debt instrument
Principal amount	$ 650
Term of debt instrument	5 years 6 months
Interest rate, stated percentage (as a percent)	2.25%
Fixed rate medium term note due 2027 \| Estimated Financial Impact
Debt instrument
Principal amount	$ 850
Term of debt instrument	10 years
Interest rate, stated percentage (as a percent)	2.875%
Fixed rate medium term note due 2047 \| Estimated Financial Impact
Debt instrument
Principal amount	$ 500
Term of debt instrument	30 years
Interest rate, stated percentage (as a percent)	3.625%
Notes Due 2028 \| Estimated Financial Impact
Debt instrument
Debt repurchases	$ 110
Principal amount	$ 330
Interest rate, stated percentage (as a percent)	6.375%
Notes Due 2037 \| Estimated Financial Impact
Debt instrument
Debt repurchases	$ 195
Principal amount	$ 750
Interest rate, stated percentage (as a percent)	5.70%
Fixed rate medium term notes repaid June 2017
Debt instrument
Principal amount			$ 650