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Commitments and Contingencies (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Sep. 30, 2018
Loss Contingencies [Line Items]
Liabilities recognized for estimated environmental costs	$ 18,600		$ 20,500
Environmental expenses	2,000	$ 2,500
Receivables from insurance carriers related to environmental matters	4,000		4,100
Gain (Loss) on Disposition of Other Assets	21,788	$ 0
Accounts Receivable [Member]
Loss Contingencies [Line Items]
Receivables from insurance carriers related to environmental matters	2,400		2,400
Other Noncurrent Assets [Member]
Loss Contingencies [Line Items]
Receivables from insurance carriers related to environmental matters	$ 1,600		$ 1,700
BridgeTex [Member]
Loss Contingencies [Line Items]
Interest in equity method investment	30.00%
Gain (Loss) on Disposition of Other Assets	$ 11,000
BridgeTex [Member] \| Indemnification Agreement [Member]
Loss Contingencies [Line Items]
Guarantees, Fair Value Disclosure	$ 5,000			$ 16,000
Powder Springs Logistics, LLC [Member]
Loss Contingencies [Line Items]
Interest in equity method investment	50.00%
Powder Springs Logistics, LLC [Member] \| Guarantee of Indebtedness of Others [Member] \| Equity Method Investee [Member]
Loss Contingencies [Line Items]
Interest in equity method investment	50.00%
Guarantor Obligations, Maximum Exposure, Undiscounted	$ 25,000
Guarantees, Fair Value Disclosure	$ 400