Amount for accounts payable to related parties.

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Amount of receivables arising from transactions with related parties due within one year or the normal operating cycle, if longer.

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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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Related Party Transactions (Details) - Director [Member] - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Targa Resource Partners L P [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Expenses from Transactions with Related Party	$ 4.7	$ 8.8
Accounts Payable, Related Parties			$ 2.0
Methvin Company [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Other Revenues from Transactions with Related Party	3.0
Accounts Receivable, Related Parties, Current	$ 1.5		$ 1.3