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The percentage points to be added upon maturity to the reference rate to compute the variable rate on the preferred stock.

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

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Date of distribution for distribution of cash or unit to limited partner of limited partnership (LP), in CCYY-MM-DD format.

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The month and year (YYYY-MM) that the dividend to be paid was declared.

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Percentage investment held by the managing member or general partner of the limited liability company (LLC) or limited partnership (LP).

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

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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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No definition available.

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Total contributions made by each class of partners (i.e., general, limited and preferred partners).

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Units contributed by each class of partners during the year. Units represent shares of ownership of the general, limited, and preferred partners.

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Amount of cash outflow in the form of ordinary dividends to preferred shareholders of the parent entity.

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The percentage rate used to calculate dividend payments on preferred stock.

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No definition available.

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The number of preferred units issued.

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Partnership Units and Related Matters (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended		3 Months Ended				6 Months Ended
	Jul. 31, 2020	Oct. 31, 2015	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Limited Partners Capital Account [Line Items]
Contributions from Targa Resources Corp.			$ 50.0			$ 190.0	$ 50.0	$ 190.0
Distributions payable date			Aug. 13, 2020	May 13, 2020	Feb. 13, 2020
Subsequent Event [Member]
Limited Partners Capital Account [Line Items]
Date of declaration for cash distribution	2020-07
Cash distribution declared per unit (in dollars per share)	$ 0.1875
Distributions to Targa Resources Corp.	$ 0.9
Distributions payable date	Aug. 17, 2020
Series A Preferred Limited Partner Units [Member]
Limited Partners Capital Account [Line Items]
Series A preferred limited partners units issued (in units)			5,000,000		5,000,000		5,000,000
Preferred units dividend percentage		9.00%					9.00%
Distribution to holders of preferred units			$ 2.8				$ 5.6
Series A Preferred Limited Partner Units [Member] \| London Interbank Offered Rate (LIBOR)
Limited Partners Capital Account [Line Items]
Percentage of variable interest rate for distribution on preferred units upon maturity		7.71%
TRC/TRP Merger [Member] \| Limited Partners [Member]
Limited Partners Capital Account [Line Items]
Percentage of capital contribution towards partner's interest maintained							98.00%
TRC/TRP Merger [Member] \| Targa Resources GP LLC [Member]
Limited Partners Capital Account [Line Items]
Percentage of general partner's interest maintained							2.00%
Contributions from Targa Resources Corp. (in units)							0
TRC/TRP Merger [Member] \| Targa Resources Corp [Member]
Limited Partners Capital Account [Line Items]
Contributions from Targa Resources Corp.			$ 50.0