Per unit of ownership amount of cash distributions paid to unit-holder of a limited partnership (LP).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-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

Name:	us-gaap_DistributionMadeToLimitedPartnerDistributionsPaidPerUnit
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

Partners' Capital and Distributions - Distributions, Class A (Details) - Cash Distribution - Class A Shares - USD ($) $ / shares in Units, $ in Millions	Nov. 14, 2019	Aug. 14, 2019	May 15, 2019	Feb. 14, 2019
Partners' Capital and Distributions
Distributions to Class A shareholders		$ 60	$ 57	$ 48
Distribution per Class A share, paid (usd per share)		$ 0.36	$ 0.36	$ 0.30
Forecast
Partners' Capital and Distributions
Distributions to Class A shareholders	$ 66
Distribution per Class A share, paid (usd per share)	$ 0.36