Employee Benefit Plans (Net Periodic Cost) (Details) (USD $)	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Employee Benefit Plans [Abstract]
Service cost	$ 428,000	$ 557,000
Interest cost	7,434,000	7,578,000
Expected return on plan assets	(3,787,000)	(3,845,000)
Amortization of prior service credit	(1,096,000)	(1,096,000)
Amortization of net loss	6,825,000	6,514,000
Net periodic cost	9,804,000	9,708,000
Contribution	7,100,000
Additional contributions	$ 27,200,000