Business Segments (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013 SegmentINF	Sep. 30, 2012
Business Segments [Abstract]
Number of reportable segments			5
Segment Gross Operating Margin [Abstract]
Revenues	$ 12,093.3	$ 10,468.7	$ 34,625.7	$ 31,511.0
Less: Operating costs and expenses	(11,273.5)	(9,659.8)	(32,061.1)	(29,136.5)
Add: Equity in income of unconsolidated affiliates	44.0	21.0	126.1	42.2
Depreciation, amortization and accretion	285.2	269.2	851.7	785.1
Non-cash asset impairment charges	15.2	43.1	53.3	57.6
Gains attributable to asset sales and insurance recoveries	(10.2)	(2.6)	(68.4)	(34.1)
Total segment gross operating margin	1,154.0	1,139.6	3,527.3	3,225.3
Reconciliation of total Segment Gross Operating Margin [Abstract]
Total segment gross operating margin	1,154.0	1,139.6	3,527.3	3,225.3
Amounts included in operating costs and expenses [Abstract]
Depreciation, amortization and accretion	(285.2)	(269.2)	(851.7)	(785.1)
Non-cash asset impairment charges	(15.2)	(43.1)	(53.3)	(57.6)
Gains attributable to asset sales and insurance recoveries	10.2	2.6	68.4	34.1
General and administrative costs	(43.9)	(41.4)	(138.9)	(130.2)
Operating income	819.9	788.5	2,551.8	2,286.5
Other expense, net	(207.7)	(198.2)	(604.2)	(499.4)
Income before income taxes	$ 612.2	$ 590.3	$ 1,947.6	$ 1,787.1