Stock-Based Compensation Plans (Restricted Shares Granted) (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2012		Jun. 30, 2012
Grant Share Amount A [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Restricted share grants, Date of Grant			Jan. 03, 2012
Restricted share grants, Shares			272,153
Restricted share grants, Market Value Per Share	$ 15.80		$ 15.80
Restricted share grants, vesting percentage			33.00%
Restricted share grants Vesting Period, in years			3 years
Grant Share Amount B [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Restricted share grants, Date of Grant			Jan. 03, 2012
Restricted share grants, vesting percentage			100.00%
Restricted stock, vesting date	January 1, 2015
Performance Share Units Granted			132,910	[1]
Performance Share Unit Market Value	$ 23.68	[1]	$ 23.68	[1]
Grant Share Amount C [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Restricted share grants, Date of Grant			Jan. 03, 2012
Restricted share grants, Shares			1,958
Restricted share grants, Market Value Per Share	$ 15.80		$ 15.80
Restricted share grants, vesting percentage			100.00%
Restricted stock, vesting date	January 1, 2014
Grant Share Amount D [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Restricted share grants, Date of Grant			Apr. 01, 2012
Restricted share grants, Shares	1,879
Restricted share grants, Market Value Per Share	$ 17.80		$ 17.80
Restricted share grants, vesting percentage			100.00%
Restricted stock, vesting date	January 1, 2014

[1] Reflects the grant of PSUs to certain of our executive officers. The estimated fair value of the PSUs on grant date was determined using a Monte Carlo simulation model. The PSUs provide for an award based on the performance of our common stock over a three-year period with the maximum award being 200% of the original awarded PSUs and the minimum amount being zero. The vested PSUs will be settled in an equivalent number of shares of our common stock unless the Compensation Committee of our Board of Directors elects to pay in cash. See Note 12 of 2011 Form 10-K.