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

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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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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- Definition

Amount of cash outflow for the payment of debt classified as other.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585

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Long-term Debt (Debt Repayments) (Details) - USD ($) $ in Millions	1 Months Ended		6 Months Ended
	May 31, 2017	Jan. 31, 2017	Jun. 30, 2017	Jun. 30, 2016
Debt Instrument [Line Items]
Repurchases and repayments of debt			$ 4,967	$ 2,551
Senior 8.875% Notes Due 2017 [Member]
Debt Instrument [Line Items]
Repurchases and repayments of debt	$ 550
Interest rate	8.875%
Senior 6.50% Notes Due 2017 [Member]
Debt Instrument [Line Items]
Repurchases and repayments of debt		$ 1,000
Interest rate		6.50%