Long-Term Debt (GO Zone Act Senior Notes Due 2029) (Details) (GO Zone 6 1/2% Senior Notes Due 2029 [Member], USD $)			12 Months Ended		1 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2011 Redeemed Prior To August 1, 2020 [Member]	Dec. 31, 2011 Redeemed On Or After August 1, 2020 [Member]	Jul. 31, 2010 Gulf Opportunity Zone Act Of 2005 [Member]	Jul. 02, 2010 Gulf Opportunity Zone Act Of 2005 [Member]
Debt Instrument [Line Items]
Face amount						$ 100,000,000
Stated interest rate	6.50%	6.50%				6.50%
Maturity date					Aug. 01, 2029
Percentage of principal required if called			100.00%	100.00%
Senior notes	100,000,000	100,000,000
Minimum debt amount guaranteed by subsidiaries	$ 5,000,000