Equity Transactions And Stock-Based Compensation Plans Narrative (Details) (USD $)	0 Months Ended	12 Months Ended				12 Months Ended				12 Months Ended			12 Months Ended			12 Months Ended	1 Months Ended	12 Months Ended
	Jul. 20, 2011	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Jul. 31, 2009	Dec. 31, 2011 Restricted Stock [Member] Years	Dec. 31, 2010 Restricted Stock [Member]	Dec. 31, 2009 Restricted Stock [Member]	Dec. 31, 2011 Restricted Stock [Member] Maximum [Member]	Dec. 31, 2011 Stock Options [Member] Years	Dec. 31, 2011 Stock Options [Member] Approved Grant of Stock Options [Member]	Jan. 31, 2012 Stock Options [Member] Approved Grant of Stock Options [Member]	Dec. 31, 2011 Restricted Stock Units (RSUs) [Member] Years	Dec. 31, 2011 Restricted Stock Units (RSUs) [Member] Approved Grant of Stock Options [Member]	Jan. 31, 2012 Restricted Stock Units (RSUs) [Member] Approved Grant of Stock Options [Member]	Dec. 31, 2011 Restricted Stock Units (RSUs) [Member] Performance-Based RSUs, 2011 [Member]	Apr. 30, 2011 Restricted Stock Units (RSUs) [Member] Performance-Based RSUs, 2010 [Member]	Dec. 31, 2011 Restricted Stock Units (RSUs) [Member] Performance-Based RSUs, 2010 [Member]	Dec. 31, 2011 Common Stock [Member]	Dec. 31, 2009 Common Stock [Member]
Class of Stock [Line Items]
Stock Issued During Period, Shares, New Issues																			6,900,000	3,820,000
Common Stock, Issuance Value Per Share	$ 14.50	$ 9.68			$ 6.75
Registration Statement, Stated Maximum Amount Available for Equity or Debt Offerings					$ 300,000,000
Proceeds from stock, net of offering costs	94,300,000	94,343,000	0	24,043,000
Registration Payment Arrangement, Available Potential Consideration		174,200,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant		2,020,889							882,903
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period						3 years				3 years	3 years		3 years	3 years		39 months		3 years
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period										10 years
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value		10,100,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value		6,500,000
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized						$ 600,000				$ 1,600,000			$ 2,600,000
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition						0.9				1.2			1.7
Share-based Compensation Arrangement by Share-based Payment Award, Additional Number of Shares Granted												470,656			407,448
Share-based Compensation Arrangement by Share-based Payment Award, Basis for Determining Award on Market Factors, Percentage		33.33%
Share-based Compensation Arrangement by Share-based Payment Award, Basis for Determining Award on Individual Performance Factors, Percentage		66.67%
Share-based Compensation Arrangement by Share-based Payment Award, Actual Achievement Level, Percentage																150.00%	86.70%
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number						281,836	329,659	427,358								139,089
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Adjusted to Performance Condition Evaluation Number																185,452
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Converted from Other Award Type						166,918											166,918
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period						233,061	160,223										55,618