Related Party Transactions - Targa - Summary of Transactions with Affiliates (Parenthetical) (Details) - Targa Resources Corp. [Member]	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Limited Partners [Member]
Related Party Transaction [Line Items]
Percentage of capital contribution towards partner's interest maintained	98.00%	98.00%	98.00%	98.00%
Targa Resources GP LLC [Member]
Related Party Transaction [Line Items]
Percentage of general partner's interest maintained	2.00%	2.00%	2.00%	2.00%

Percentage investment held by the managing member or general partner of the limited liability company (LLC) or 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 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055

+ Details

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- Definition

Percentage investment held by members or limited partners of limited liability company (LLC) or limited partnership (LP).

+ References

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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.

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- Details

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- Details

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