Accounts Payable and Accrued Liabilities (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Components of accounts payable and accrued liabilities [Abstract]
Commodities	$ 445.8	$ 416.7
Other goods and services	172.7	111.1
Interest	58.3	37.3
Compensation and benefits	21.6	46.1
Income and other taxes	19.0	11.7
Other	19.4	15.6
Accounts payable and accrued liabilities	736.8	638.5
Targa Resources Partners LP [Member]
Components of accounts payable and accrued liabilities [Abstract]
Commodities	445.8	416.7
Other goods and services	169.8	108.9
Interest	57.0	37.3
Compensation and benefits	3.2	1.3
Income and other taxes	20.0	13.6
Other	15.0	14.9
Accounts payable and accrued liabilities	710.8	592.7
TRC Non Partnership [Member]
Components of accounts payable and accrued liabilities [Abstract]
Commodities	0	0
Other goods and services	2.9	2.2
Interest	1.3	0
Compensation and benefits	18.4	44.8
Income and other taxes	(1.0)	(1.9)
Other	4.4	0.7
Accounts payable and accrued liabilities	$ 26.0	$ 45.8