Distributions in excess of net income.

No definition available.

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- Definition

Schedule of partners capital.

+ References

No definition available.

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- Definition

The total amount of dividends declared in the period for each class of stock and the contractual amount of dividends (or interest on participating income bonds) that must be paid for the period (for example, unpaid cumulative dividends). Dividends declared in the current period do not include dividends declared in respect of prior-period unpaid cumulative dividends. Preferred dividends that are cumulative only if earned are deducted only to the extent that they are earned.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 60B
-URI http://asc.fasb.org/extlink&oid=96947427&loc=SL5780133-109256

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 60A
-URI http://asc.fasb.org/extlink&oid=96947427&loc=SL5780132-109256

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 60
-URI http://asc.fasb.org/extlink&oid=96947427&loc=d3e2740-109256

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 66
-URI http://asc.fasb.org/extlink&oid=96947427&loc=d3e2814-109256

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- Definition

Amount of cash distribution paid to unit-holder of limited partnership (LP).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70434-108055

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Cash dividends declared or paid to each outstanding limited partnership and general partnership unit during the reporting period.

+ References

No definition available.

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- Definition

Aggregate amount of net income allocated to limited partners.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187171-122770

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Partners' Capital (Allocations of Net Income) (Details) - USD ($) $ / shares in Units, $ in Millions														12 Months Ended
	Feb. 14, 2018	Nov. 14, 2017	Aug. 15, 2017	May 16, 2017	Feb. 16, 2017	Nov. 15, 2016	Aug. 15, 2016	May 16, 2016	Feb. 16, 2016	Nov. 27, 2015	Aug. 28, 2015	May 29, 2015	Feb. 27, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Schedule of Partners' Capital [Line Items]
Distribution Made to Limited Partner, Cash Distributions Paid		$ 82	$ 82	$ 82	$ 81	$ 79	$ 79	$ 78	$ 70	$ 47	$ 29	$ 23	$ 21	$ 431	$ 386	$ 120
Cash distribution per unit (in dollars per share)														$ 3.3020	$ 3.2938	$ 2.8851
General Partner [Member]
Schedule of Partners' Capital [Line Items]
Distribution Made to Limited Partner, Cash Distributions Paid		$ 22	$ 21	$ 21	$ 21	$ 20	$ 20	$ 20	$ 17	$ 8	$ 3	$ 1	$ 1
Common Units [Member]
Schedule of Partners' Capital [Line Items]
Distributions														$ 328	$ 317	$ 156
Distributions in excess of net income														(293)	(809)	(112)
Limited partners' interest in net income														35	(492)	44
Subordinated Units [Member]
Schedule of Partners' Capital [Line Items]
Distributions														0	0	23
Distributions in excess of net income														0	0	(12)
Limited partners' interest in net income														$ 0	$ 0	$ 11
Subsequent Event [Member]
Schedule of Partners' Capital [Line Items]
Distribution Made to Limited Partner, Cash Distributions Paid	$ 82
Subsequent Event [Member] \| General Partner [Member]
Schedule of Partners' Capital [Line Items]
Distribution Made to Limited Partner, Cash Distributions Paid	$ 21