CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY (Unaudited) (USD $) In Millions	Common Stock [Member] USD ($)	Additional Paid-in Capital [Member] USD ($)	Retained Earnings [Member] USD ($)	Accumulated Other Comprehensive Loss [Member] USD ($)	Noncontrolling Interest [Member] USD ($)	Redeemable Noncontrolling Interest [Member] USD ($)	Number of common shares outstanding [Member]	Total USD ($)
Balance at Dec. 31, 2011	$ 0.8	$ 521.8	$ 596.2	$ (29.6)	$ 0.2	$ 0		$ 1,089.4
Balance (in shares) at Dec. 31, 2011							81.0
Comprehensive income (loss)	0	0	(1.2)	9.3	0.2	0		8.3
Issuance of restricted stock to employees, net of forfeitures	0	0	0	0	0	0		0
Issuance of restricted stock to employees, net of forfeitures (in shares)							2.1
Shares withheld for taxes upon vesting of restricted stock	0	(0.1)	(0.2)	0	0	0		(0.3)
Shares withheld for taxes upon vesting of restricted stock (in shares)							0
Amortization of restricted stock	0	9.3	0	0	0	0		9.3
Distributions to noncontrolling interests	0	0	0	0	(0.2)	0		(0.2)
Tax effects from vesting of restricted stock	0	1.4	0	0	0	0		1.4
Tax effects of expired employee stock options	0	(1.3)	0	0	0	0		(1.3)
Dividends on common stock ($0.05 per share)	0	0	(3.9)	0	0	0		(3.9)
Repurchase of common shares	0	(4.2)	(4.7)	0	0	0		(8.9)
Repurchase of common shares (in shares)							(1.0)
Balance at Mar. 31, 2012	0.8	526.9	586.2	(20.3)	0.2	0		1,093.8
Balance (in shares) at Mar. 31, 2012							82.1
Balance at Dec. 31, 2012	0.8	520.8	501.1	(17.9)	0.9	0.6		1,005.7
Balance (in shares) at Dec. 31, 2012							79.2
Comprehensive income (loss)	0	0	0.5	(8.9)	0.4	0		(8.0)
Issuance of restricted stock to employees, net of forfeitures	0	0	0	0	0	0		0
Issuance of restricted stock to employees, net of forfeitures (in shares)							2.1
Shares withheld for taxes upon vesting of restricted stock	0	(1.0)	(1.0)	0	0	0		(2.0)
Shares withheld for taxes upon vesting of restricted stock (in shares)							(0.2)
Amortization of restricted stock	0	10.9	0	0	0	0		10.9
Distributions to noncontrolling interests	0	0	0	0	(0.2)	0		(0.2)
Tax effects from vesting of restricted stock	0	(0.7)	0	0	0	0		(0.7)
Tax effects of cancelled restricted stock	0	(4)	0	0	0	0		(4)
Dividends on common stock ($0.05 per share)	0	0	(4.0)	0	0	0		(4.0)
Repurchase of common shares	0	(4.7)	(4.3)	0	0	0		(9.0)
Repurchase of common shares (in shares)							(0.8)
Balance at Apr. 06, 2013	$ 0.8	$ 521.3	$ 492.3	$ (26.8)	$ 1.1	$ 0.6		$ 988.7
Balance (in shares) at Apr. 06, 2013							80.3