Debt Obligations - Schedule of Contractual Maturities of Debt Obligations (Details) $ in Millions	Dec. 31, 2016 USD ($)
Contractual Obligation [Line Items]
Total	$ 4,916.8
2017	275.0
2018	250.5
2019	749.4
2020	425.0
2021	6.5
After 2021	3,210.4
Accounts Receivable Securitization Facility [Member] \| Targa Resources Partners LP [Member]
Contractual Obligation [Line Items]
Total	275.0
2017	275.0
2018	0.0
2019	0.0
2020	0.0
2021	0.0
After 2021	0.0
Secured Debt [Member]
Contractual Obligation [Line Items]
Total	160.0
2017	0.0
2018	0.0
2019	0.0
2020	0.0
2021	0.0
After 2021	160.0
Senior Unsecured Notes [Member] \| Targa Resources Partners LP [Member]
Contractual Obligation [Line Items]
Total	4,056.8
2017	0.0
2018	250.5
2019	749.4
2020	0.0
2021	6.5
After 2021	3,050.4
TRC Senior Secured Revolving Credit Facility [Member]
Contractual Obligation [Line Items]
Total	275.0
2017	0.0
2018	0.0
2019	0.0
2020	275.0
2021	0.0
After 2021	0.0
TRP Revolver [Member]
Contractual Obligation [Line Items]
Total	150.0
2017	0.0
2018	0.0
2019	0.0
2020	150.0
2021	0.0
After 2021	$ 0.0

Contractual obligation.

No definition available.

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Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments.

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No definition available.

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- Definition

Amount of contractual obligation due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

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Amount of contractual obligation due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

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Amount of contractual obligation due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

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- Definition

Amount of contractual obligation due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

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- Definition

Amount of contractual obligation due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

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Amount of contractual obligation due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

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