Commitments and Contingencies Crude Oil Releases (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Macedonia Crude Oil Release [Member]
Loss Contingencies [Line Items]
Cost incurred for environmental remediation	$ 0	$ 0	$ 0	$ 0
Accrual for expected fines and penalties	1.3		1.3
Maximum Exposure for Environmental Remediation under Omnibus Agreement			0.3
Magnolia Station Spill [Member]
Loss Contingencies [Line Items]
Cost incurred for environmental remediation				0.3
Accrual for expected fines and penalties	0.1		0.1
Maximum Exposure for Environmental Remediation under Omnibus Agreement			0.3
Haynesville Crude Oil Release [Member]
Loss Contingencies [Line Items]
Cost incurred for environmental remediation	0		1.0
Accrual for expected fines and penalties	1.3		1.3
Maximum Exposure for Environmental Remediation under Omnibus Agreement			$ 1.0