Debt (8.25% Senior Suborinated Notes Due 2016) (Details) (8.25% Senior subordinated notes due 2016, USD $)			12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2011 Unsecured Debt	Dec. 31, 2006 Unsecured Debt	Dec. 31, 2011 Unsecured Debt November 1, 2011 through October 31, 2012	Dec. 31, 2011 Unsecured Debt November 1, 2012 through October 31, 2013	Dec. 31, 2011 Unsecured Debt November 1, 2013 through October 31, 2014	Dec. 31, 2011 Unsecured Debt November 1, 2014 and thereafter
Debt Instrument
Principal amount of debt issued				$ 200,000,000
Interest rate on debt instrument (as a percent)	8.25%	8.25%		8.25%
Net proceeds from issuance senior subordinated debt				$ 196,000,000
Senior Notes, Expressed As Percentage Of Principal Amount Redeemed, Plus Accured and Unpaid Interest
Redemption price, as a percentage of the principal or face amount of the given debt instrument, that the Company must pay upon redemption					104.125%	102.75%	101.375%	100.00%
Debt Instrument redemption price percentage of principal amount plus make whole premium, plus accrued and unpaid interest (as a percent)			100.00%