Employee Benefit Plans (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Defined Benefit Plan Disclosure [Line Items]
Interest cost	$ 806,000	$ 957,000	$ 2,406,000	$ 2,728,000
Expected return on plan assets	(935,000)	(730,000)	(2,635,000)	(2,212,000)
Actuarial (gain)/loss	513,000	48,000	1,563,000	79,000
Total for defined benefit plans	384,000	275,000	1,334,000	595,000
Supplemental executive retirement plan	923,000	648,000	2,723,000	1,624,000
Defined contribution plans	3,213,000	2,704,000	11,568,000	10,734,000
Total	4,520,000	3,627,000	15,625,000	12,953,000
Employer contributions to SERP			600,000
Expected contributions to SERP	4,000,000		4,000,000
Company contributions			$ 9,200,000