Stock-Based Compensation (Details) (USD $)	9 Months Ended			12 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2012 Restricted shares [Member]	Sep. 30, 2012 Stock options [Member]	Dec. 31, 2011 Stock options [Member]	Sep. 30, 2012 Performance Shares [Member]	Sep. 30, 2012 Term 1 [Member]	Sep. 30, 2012 Term 2 [Member]	Sep. 30, 2012 Term 3 [Member]	Sep. 30, 2012 Term 4 [Member]	Sep. 30, 2012 Stock Compensation Plan [Member]	Sep. 30, 2011 Stock Compensation Plan [Member]	Sep. 30, 2012 Stock Compensation Plan [Member] Restricted shares [Member]	Sep. 30, 2011 Stock Compensation Plan [Member] Restricted shares [Member]	Sep. 30, 2012 Stock Compensation Plan [Member] Stock options [Member]	Sep. 30, 2011 Stock Compensation Plan [Member] Stock options [Member]
Restricted Stock Award, Forfeitures [Abstract]
Restricted Stock, Balance, January 1, 2012 (in shares)		301,373
Restricted Stock, Granted, Shares		260,846
Restricted Stock, Vested, Shares		(58,292)
Restricted Stock, Expired, Shares		0
Restricted Stock, Forfeited, Shares		(76,974)
Restricted Stock Outstanding, June 30, 2012 (in shares)		426,953
Restricted Stock, Weighted Average Grant Price, Balance, January 1, 2012 (in dollars per share)		$ 17.82
Restricted Stock, Granted, Weighted Average Grant Price		$ 19.86
Restricted Stock, Vested, Weighted Average Grant Price		$ 23.43
Restricted Stock, Expired, Weighted Average Grant Price		$ 0.00
Restricted Stock, Forfeited, Weighted Average Exercise Price		$ 17.02
Restricted Stock Outstanding, Weighted Average Grant Price, Balance, June 30, 2012 (in dollars per share		$ 18.45
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Stock Options, Shares, Oustanding, January 1, 2012 (in shares)			15,800
Stock Options, Granted, Shares			0
Stock Options, Exercised, Shares			0
Stock Options, Expired, Shares			(973)
Stock Options, Cancelled, Shares			(1,954)
Stock Options, Shares, Oustanding, June 30, 2012 (in shares)			12,873	15,800
Stock Options, Weighted Average Grant Price, Balance, January 1, 2012 (in dollars per share)			$ 1,393.65
Stock Options Granted, Weighted Average Grant Price			$ 0.00
Stock Options, Exercised, Weighted Average Grant Price			$ 0.00
Stock Options, Expired, Weighted Average Grant Price			$ 1,519.35
Stock Options, Cancelled, Weighted Average Exercise Price			$ 1,247.21
Stock Options, Weighted Average Grant Price, Outstanding, June 30, 2012 (in dollars per share)			$ 1,406.37	$ 1,393.65
Stock Options, Shares Exercisable, June 30, 2012			12,470
Stock Options, Weighted Average Exercise Price, June 30, 2012			$ 1,447.88
Weighted Average Contractual Life And Aggregate Intrinsic Value Of Stock Options [Abstract]
Stock Options, Outstanding, Weighted Average Life			1 year 5 months 18 days	2 years 1 month 6 days
Stock Options, Outstanding, Intrinsic Value			$ 0	$ 0
Stock Options, Exercisable, Weighted Average Life			1 year 5 months 18 days	2 years 1 month 6 days
Stock Options, Exercisable, Intrinsic Value			0	0
Shares Available for Grant					5,398,091
Stock-based Compensation Expense										2,756,000	2,949,000	2,719,000	2,723,000	37,000	226,000
Unrecognized Equity Compensation	$ 5,500,000
Unrecognized Equity Compensation, Weighted Average Period for Recognition	2 years 2 months 24 days
Long-Term Incentive Plans, Vesting Periods						4 years	6 years	8 years	10 years