Derivative Instruments, Hedging Activities and Fair Value Measurements, Nonrecurring Fair Value Measurements (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Assets, Fair Value Disclosure [Abstract]
Non-cash asset impairment charges	$ 92.6		$ 63.4		$ 27.8
Long-lived Assets Disposed of Other Than By Sale [Member]
Assets, Fair Value Disclosure [Abstract]
Non-cash asset impairment charges	79.4	[1]	56.5	[2]
Long-lived Assets Held and Used [Member]
Assets, Fair Value Disclosure [Abstract]
Non-cash asset impairment charges	9.0		2.6
Long-lived Assets Disposed of By Sale [Member]
Assets, Fair Value Disclosure [Abstract]
Non-cash asset impairment charges	9.0		4.3
Property, Plant and Equipment [Member]
Assets, Fair Value Disclosure [Abstract]
Non-cash asset impairment charges	92.6
NGL Pipelines and Services [Member]
Assets, Fair Value Disclosure [Abstract]
Non-cash asset impairment charges	30.6		16.3		11.3
Onshore Natural Gas Pipelines And Services [Member]
Assets, Fair Value Disclosure [Abstract]
Non-cash asset impairment charges	0		29.2		10.4
Onshore Crude Oil Pipelines and Services [Member]
Assets, Fair Value Disclosure [Abstract]
Non-cash asset impairment charges	30.1		10.6		0
Offshore Pipelines And Services [Member]
Assets, Fair Value Disclosure [Abstract]
Non-cash asset impairment charges	18.0		4.0		5.5
Offshore Natural Gas Gathering Systems [Member]
Assets, Fair Value Disclosure [Abstract]
Non-cash asset impairment charges	4.8
Petrochemical and Refined Products Services [Member]
Assets, Fair Value Disclosure [Abstract]
Non-cash asset impairment charges	18.7		3.3		0.6
Fair Value [Member]
Assets, Fair Value Disclosure [Abstract]
Non-cash asset impairment charges	97.4		63.4		27.8
Fair Value, Measurements, Nonrecurring [Member] | Long-lived Assets Disposed of Other Than By Sale [Member]
Assets, Fair Value Disclosure [Abstract]
Assets, fair value	0	[1]	0.8	[2]
Fair Value, Measurements, Nonrecurring [Member] | Long-lived Assets Held and Used [Member]
Assets, Fair Value Disclosure [Abstract]
Assets, fair value	44.6		2.2
Fair Value, Measurements, Nonrecurring [Member] | Long-lived Assets Disposed of By Sale [Member]
Assets, Fair Value Disclosure [Abstract]
Assets, fair value	0.6		0
Fair Value, Measurements, Nonrecurring [Member] | Level 1 [Member] | Long-lived Assets Disposed of Other Than By Sale [Member]
Assets, Fair Value Disclosure [Abstract]
Assets, fair value	0	[1]	0	[2]
Fair Value, Measurements, Nonrecurring [Member] | Level 1 [Member] | Long-lived Assets Held and Used [Member]
Assets, Fair Value Disclosure [Abstract]
Assets, fair value	0		0
Fair Value, Measurements, Nonrecurring [Member] | Level 1 [Member] | Long-lived Assets Disposed of By Sale [Member]
Assets, Fair Value Disclosure [Abstract]
Assets, fair value	0		0
Fair Value, Measurements, Nonrecurring [Member] | Level 2 [Member] | Long-lived Assets Disposed of Other Than By Sale [Member]
Assets, Fair Value Disclosure [Abstract]
Assets, fair value	0	[1]	0	[2]
Fair Value, Measurements, Nonrecurring [Member] | Level 2 [Member] | Long-lived Assets Held and Used [Member]
Assets, Fair Value Disclosure [Abstract]
Assets, fair value	0		0
Fair Value, Measurements, Nonrecurring [Member] | Level 2 [Member] | Long-lived Assets Disposed of By Sale [Member]
Assets, Fair Value Disclosure [Abstract]
Assets, fair value	0		0
Fair Value, Measurements, Nonrecurring [Member] | Level 3 [Member] | Long-lived Assets Disposed of Other Than By Sale [Member]
Assets, Fair Value Disclosure [Abstract]
Assets, fair value	0	[1]	0.8	[2]
Fair Value, Measurements, Nonrecurring [Member] | Level 3 [Member] | Long-lived Assets Held and Used [Member]
Assets, Fair Value Disclosure [Abstract]
Assets, fair value	44.6		2.2
Fair Value, Measurements, Nonrecurring [Member] | Level 3 [Member] | Long-lived Assets Disposed of By Sale [Member]
Assets, Fair Value Disclosure [Abstract]
Assets, fair value	$ 0.6		$ 0

[1] Our non-cash asset impairment charges for the year ended December 31, 2013 primarily represent the abandonment of crude oil and natural gas pipeline segments in Texas, Oklahoma and the Gulf of Mexico, certain refined products terminal assets in Texas, an NGL storage cavern in Arizona and an NGL fractionator and storage caverns in Ohio.

[2] Our non-cash asset impairment charges for the year ended December 31, 2012 primarily represent the abandonment of crude oil and natural gas pipeline segments in Texas and the Gulf of Mexico.