Long-Term Incentive Plans (Stock Options Outstanding) (Details) (USD $)	3 Months Ended		12 Months Ended
	Mar. 31, 2010	Mar. 31, 2009	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Long-Term Incentive Plans [Abstract]
Outstanding at beginning of year, Number of Shares	7,044,820	6,312,194	6,650,947	7,044,820	6,312,194
Number of options granted	1,100,000	1,900,000		1,100,000	1,900,000
Expired or canceled, Number of Shares			(225,874)	(1,493,873)	(1,167,374)
Outstanding at end of year, Number of Shares			6,425,073	6,650,947	7,044,820
Exercisable at end of year, Number of Shares			2,211,878	2,050,252	2,006,620
Outstanding at beginning of year, Weighted Avg. Price per Share	$ 25.3110	$ 34.9822	$ 22.1713	$ 25.3110	$ 34.9822
Granted, Weighted Avg. Price per Share				$ 5.0500	$ 4.0200
Expired or canceled, Weighted Avg. Price per Share			$ 46.0164	$ 24.3703	$ 42.9522
Outstanding at end of year, Weighted Avg. Price per Share			$ 21.3330	$ 22.1713	$ 25.3110
Exercisable at end of year	$ 5.05	$ 4.02	$ 46.1478	$ 53.1172	$ 50.0301
Weighted average fair value per share of options granted during the year, Weighted Avg. Price per Share				$ 3.79	$ 2.61