Earnings per Share (EPS) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended			6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013		Jun. 30, 2014	Jun. 30, 2013
Earnings per Share (EPS) (Textuals) [Abstract]
Antidilutive shares excluded from EPS calculation	3.1	3.3		4.4	3.3
EPS numerator:
(Loss) income from continuing operations, net of income taxes	$ (72.0)	$ 101.4		$ (116.3)	$ 91.1
Less: Net income (loss) attributable to noncontrolling interests	2.1	(3.2)		6.5	0.8
(Loss) income from continuing operations attributable to common stockholders, before allocation of earnings to participating securities	(74.1)	104.6		(122.8)	90.3
Less: Earnings allocated to participating securities	0.3	0.7		0.5	0.2
(Loss) income from continuing operations attributable to common stockholders, after allocation of earnings to participating securities	(74.4)	103.9	[1]	(123.3)	90.1	[1]
Income (loss) from discontinued operations, net of income taxes	0.8	(14.3)		1.0	(23.4)
Less: Loss from discontinued operations allocated to participating securities	0	(0.1)		0	(0.2)
Income (loss) from discontinued operations attributable to common stockholders, after earnings allocated to participating securities	0.8	(14.2)	[1]	1.0	(23.2)	[1]
Net (loss) income attributable to common stockholders, after earnings allocated to participating securities	(73.6)	89.7	[1]	(122.3)	66.9	[1]
EPS denominator:
Weighted average shares outstanding - basic	268.0	266.9		267.9	266.9
Impact of dilutive securities	0	0.6		0	0.5
Weighted average shares outstanding - diluted	268.0	267.5		267.9	267.4
Basic EPS attributable to common stockholders:
(Loss) income from continuing operations	$ (0.28)	$ 0.39		$ (0.46)	$ 0.34
Income (loss) from discontinued operations	$ 0.01	$ (0.06)		$ 0.00	$ (0.09)
Net (loss) income attributable to common stockholders	$ (0.27)	$ 0.33		$ (0.46)	$ 0.25
Diluted EPS attributable to common stockholders:
(Loss) income from continuing operations	$ (0.28)	$ 0.39		$ (0.46)	$ 0.33
Income (loss) from discontinued operations	$ 0.01	$ (0.06)		$ 0.00	$ (0.08)
Net (loss) income attributable to common stockholders	$ (0.27)	$ 0.33		$ (0.46)	$ 0.25
Reallocation adjustment for participatory securities		$ 0.1			$ 0.1

[1] The reallocation adjustment for participating securities to arrive at the numerator used to calculate diluted EPS was less than $0.1 million for the three and six months ended June 30, 2013.