Stock-Based Incentive Plans (Tables)

12 Months Ended

Dec. 31, 2012

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs

The following table summarizes the Company's stock-based compensation expense included as a component of general and administrative expenses in the consolidated financial statements:

	Year Ended December 31,
	2012			2011			2010
	(In millions)
Total stock-based compensation:
Equity classified awards	$	11.4		$	9.5		$	13.1
Liability classified awards	4.9			1.1			2.1
Total pre-tax compensation expense	16.3			10.6			15.2
Book tax benefit	(6.2		)	(4.2		)	(6.0		)
Total stock-based compensation expense, net of tax	$	10.1		$	6.4		$	9.2

Schedule of Share-based Compensation, Stock Options, Activity

Stock option activity for the years ended December 31, 2012, 2011 and 2010 is summarized as follows:

	Number of Shares under Option		Weighted Average Exercise Price Per Share		Weighted Average Remaining Contractual Term (in Years)	Aggregate Intrinsic Value
Outstanding at December 31, 2009	1,659,100		$	21.30
Granted	415,804		31.26
Exercised	(475,705	)	16.75
Forfeited	(50,222	)	25.84
Expired	(25,267	)	44.93
Outstanding at December 31, 2010	1,523,710		24.90
Granted	233,449		53.04
Exercised	(393,075	)	17.11
Forfeited	(42,593	)	27.89
Expired	(2,851	)	47.08
Outstanding at December 31, 2011	1,318,640		32.06
Granted	147,674		51.63
Exercised	(455,217	)	20.91
Forfeited	(39,381	)	46.97
Expired	(13,470	)	38.64
Outstanding at December 31, 2012	958,246		$	39.67	6.55	$	25,355,000
Vested and Expected to Vest at December 31, 2012	924,500		$	39.29	6.47	$	24,791,000
Exercisable at December 31, 2012	601,522		$	35.57	5.52	$	18,383,000

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions

The following table summarizes the assumptions used to value options granted in the respective periods:

	2012			2011			2010
Risk free interest rate	0.9		%	1.8		%	2.2		%
Weighted average historical volatility	84.5		%	79.1		%	80.4		%
Dividend yield	—		%	—		%	—		%
Expected years until exercise	4.7			4.6			4.8
Forfeitures	11.0		%	11.0		%	11.0		%
Weighted average fair value of options granted	$	33.53		$	34.31		$	19.93

Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity

Activity in equity classified awards of restricted stock and restricted stock units for the years ended December 31, 2012, 2011 and 2010 is as follows:

	Shares of Restricted Stock		Weighted Average Grant-Date Per Share Fair Value		Restricted Stock Units		Weighted Average Grant-Date Per Share Fair Value
Outstanding at December 31, 2009	650,323		$	33.09	—		$	—
Granted	209,505		30.52		20,000		29.32
Released	(159,893	)	48.18		(2,000	)	29.32
Forfeited	(33,691	)	34.16		—		—
Outstanding at December 31, 2010	666,244		28.62		18,000		29.32
Granted	164,632		53.03		—		—
Released	(287,735	)	37.82		—		—
Forfeited	(56,608	)	31.56		—		—
Outstanding at December 31, 2011	486,533		31.08		18,000		29.32
Granted	137,852		52.23		19,152		52.23
Released	(179,465	)	13.83		(3,910	)	40.58
Forfeited	(98,357	)	44.40		—		—
Outstanding at December 31, 2012	346,563		$	44.74	33,242		$	41.19

Schedule of Share-based Compensation, Restricted Stock Units Award Activity

Activity in liability classified awards of restricted stock units for the years ended December 31, 2012, 2011 and 2010 is as follows:

	Cash-Settled Restricted Stock Units		Weighted Average Per Share Fair Value
Outstanding at December 31, 2009	—		$	—
Granted	29,000		61.07
Released	(3,000	)	33.67
Outstanding at December 31, 2010	26,000		64.23
Granted	15,957		64.30
Released	—		—
Outstanding at December 31, 2011	41,957		64.26
Granted	—		—
Released	(4,773	)	49.66
Outstanding at December 31, 2012	37,184		$	66.13