Property, Plant and Equipment and Intangible Assets (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Feb. 27, 2015	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 11,624.6		$ 6,521.1
Accumulated depreciation	(1,791.6)		(1,696.5)
Property, plant and equipment, net	9,833.0		4,824.6
Finite-Lived Intangible Assets [Line Items]
Intangible assets	1,716.6		681.8
Accumulated amortization	(114.2)		(89.9)
Intangible assets, net	1,602.4		591.9
Estimated useful lives	20 years
Preliminary value of intangible assets acquired	1,035.0	1,035.0
Amortization period of acquired intangible assets used for preparing financial statements	1 month
Estimated annual amortization expense for intangible assets [Abstract]
2015	123.2
2016	140.1
2017	133.3
2018	119.5
2019	108.6
Gathering Systems [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	6,113.8		2,588.6
Gathering Systems [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	5 years
Gathering Systems [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	40 years
Processing and Fractionation Facilities [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	2,931.2		1,890.7
Processing and Fractionation Facilities [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	5 years
Processing and Fractionation Facilities [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	40 years
Terminaling and Storage Facilities [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	1,043.0		1,038.9
Terminaling and Storage Facilities [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	5 years
Terminaling and Storage Facilities [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	25 years
Transportation Assets [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	432.9		359.0
Transportation Assets [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	10 years
Transportation Assets [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	25 years
Other Property, Plant and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	220.1		149.3
Other Property, Plant and Equipment [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	3 years
Other Property, Plant and Equipment [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	40 years
Land [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	101.4		95.6
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	782.2		399.0
Targa Resources Partners LP [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	11,617.8		6,514.3
Accumulated depreciation	(1,784.9)		(1,689.7)
Property, plant and equipment, net	9,832.9		4,824.6
Finite-Lived Intangible Assets [Line Items]
Intangible assets	1,716.6		681.8
Accumulated amortization	(114.2)		(89.9)
Intangible assets, net	1,602.4		591.9
Targa Resources Partners LP [Member] | Gathering Systems [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	6,113.8		2,588.6
Targa Resources Partners LP [Member] | Processing and Fractionation Facilities [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	2,924.6		1,884.1
Targa Resources Partners LP [Member] | Terminaling and Storage Facilities [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	1,043.0		1,038.9
Targa Resources Partners LP [Member] | Transportation Assets [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	432.9		359.0
Targa Resources Partners LP [Member] | Other Property, Plant and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	219.9		149.1
Targa Resources Partners LP [Member] | Land [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	101.4		95.6
Targa Resources Partners LP [Member] | Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	782.2		399.0
TRC Non Partnership [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	6.8		6.8
Accumulated depreciation	(6.7)		(6.8)
Property, plant and equipment, net	0.1		0
Finite-Lived Intangible Assets [Line Items]
Intangible assets	0		0
Accumulated amortization	0		0
Intangible assets, net	0		0
TRC Non Partnership [Member] | Gathering Systems [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	0		0
TRC Non Partnership [Member] | Processing and Fractionation Facilities [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	6.6		6.6
TRC Non Partnership [Member] | Terminaling and Storage Facilities [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	0		0
TRC Non Partnership [Member] | Transportation Assets [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	0		0
TRC Non Partnership [Member] | Other Property, Plant and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	0.2		0.2
TRC Non Partnership [Member] | Land [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	0		0
TRC Non Partnership [Member] | Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 0		$ 0