CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) [Abstract]
Revenues	$ 1,397.8	$ 1,645.8
Costs and expenses:
Product purchases	1,137.5	1,384.2
Operating expenses	86.1	71.6
Depreciation and amortization expenses	64.0	47.4
General and administrative expenses	36.3	34.9
Income from operations	73.9	107.7
Other income (expense):
Interest expense, net	(32.1)	(30.5)
Equity earnings	1.6	2.1
Other	(0.2)	0
Income before income taxes	43.2	79.3
Income tax expense:
Current	(9.2)	(8.7)
Deferred	(0.2)	(1.4)
Income tax expense total	(9.4)	(10.1)
Net income	33.8	69.2
Less: Net income attributable to noncontrolling interests	20.4	59.6
Net income available to common shareholders	$ 13.4	$ 9.6
Net income available per common share - basic (in dollars per share)	$ 0.32	$ 0.23
Net income available per common share - diluted (in dollars per share)	$ 0.32	$ 0.23
Weighted average shares outstanding - basic (in shares)	41.6	41.0
Weighted average shares outstanding - diluted (in shares)	42.0	41.8