Stock-Based Incentive Plans Stock-Based Compensation Expense (Details) (USD $)	12 Months Ended
	Dec. 31, 2011 year	Dec. 31, 2010	Dec. 31, 2009
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Pre-tax compensation expense	$ 10,600,000	$ 15,200,000	$ 10,700,000
Book tax benefit	(4,200,000)	(6,000,000)	(4,200,000)
Total stock-based compensation expense, net of tax	6,400,000	9,200,000	6,500,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding, Beginning	1,523,710	1,659,100	933,939
Granted	233,449	415,804	1,016,750
Excercised	(393,075)	(475,705)	(15,500)
Forfeited	(42,593)	(50,222)	(222,923)
Expired	(2,851)	(25,267)	(53,166)
Outstanding, Ending	1,318,640	1,523,710	1,659,100
Vested and Expected to Vest	1,143,491
Exercisable	620,687
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Weighted Avg Share Prince, Beginning	$ 24.90	$ 21.30	$ 36.37
Weighted Avg Share Price, Granted	$ 53.04	$ 31.26	$ 8.22
Weighted Avg Share Price, Exercised	$ 17.11	$ 16.75	$ 20.87
Weighted Avg Share Price, Forfeited	$ 27.89	$ 25.84	$ 20.35
Weighted Avg Share Price, Expired	$ 47.08	$ 44.93	$ 40.07
Weighted Avg Share Prince, Ending	$ 32.06	$ 24.90	$ 21.30
Vested and expected to vest, weighted avg share price	$ 32.75
Exercisable, weighted avg share price	$ 34.21
Options, Outstanding, Weighted Average Remaining Contractual Term	6.74
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Weighted Average Remaining Contractual Term	6.53
Excercisable Weighted Average Remaining Contractual Term	5.07
Options, Outstanding, Intrinsic Value	17,110,000
Options, Vested and Expected to Vest, Outstanding, Aggregate Intrinsic Value	13,980,000
Options, Exercisable, Intrinsic Value	5,980,000
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Total Intrinsic Value	14,600,000	12,000,000	100,000
Employee Service Share-based Compensation, Cash Received from Exercise of Stock Options	6,700,000	8,000,000	300,000
Tax Benefit from Stock Options Exercised	6,000,000	2,700,000	500,000
Employee Stock Option [Member]
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized	7,600,000
Unrecognized Compensation Cost Related to Restricted Stock and RSUs Expected Recognized Over a Weighted Average Period	P1.23Y
Restricted Stock Units (RSUs) [Member]
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized	$ 7,500,000
Unrecognized Compensation Cost Related to Restricted Stock and RSUs Expected Recognized Over a Weighted Average Period	P1.43Y