Consolidated Balance Sheets (USD $) In Millions, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Assets
Cash and cash equivalents	$ 7.7	$ 5.2
Accounts receivable	364.3	412.6
Inventory	39.8	73.6
Assets from price risk management activities	10.1	14.5
Prepaid expenses and other current assets	29.4	16.1
Total current assets	451.3	522.0
Property, plant and equipment (Note 3)	4,183.7	4,108.7
Less: accumulated depreciation and depletion	245.3	203.4
Property, plant and equipment, net	3,938.4	3,905.3
Intangible assets (Note 3)	1,471.2	1,466.4
Less: accumulated amortization	132.9	106.0
Intangible assets, net	1,338.3	1,360.4
Goodwill	2,548.6	2,552.2
Investment in unconsolidated affiliates (Note 5)	171.1	151.4
Other assets	32.8	31.9
Total assets	8,480.5	8,523.2
Current liabilities:
Accounts payable	317.4	379.0
Accrued expenses and other liabilities	183.5	177.1
Liabilities from price risk management activities	6.0	34.9
Current portion of long-term debt (Note 9)	14.0	5.1
Total current liabilities	520.9	596.1
Long-term debt, less current portion (Note 9)	2,377.3	2,260.9
Other long-term liabilities	140.6	140.4
Deferred income taxes	13.4	17.2
Partners’ capital (Note 10):
Partners’ capital (186,521,737 and 185,274,279 limited partner units issued and outstanding at March 31, 2014 and December 31, 2013)	815.1	831.6
Partners' Capital	815.1	831.6
Partners' Capital Attributable to Noncontrolling Interest	4,613.2	4,677.0
Total partners’ capital	5,428.3	5,508.6
Total liabilities and partners’ capital	$ 8,480.5	$ 8,523.2