Pension and Other Postretirement Benefits (Details 2) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2012
Net periodic benefit cost and other amounts recognized in accumulated other comprehensive loss:
Reduction in certain retiree medical benefits recognized in other comprehensive income			$ 13,400,000
Pension Plans
Net periodic benefit cost and other amounts recognized in accumulated other comprehensive loss:
Service cost for benefits earned during the period	3,100,000	2,800,000	9,300,000	8,500,000
Interest cost on projected benefit obligation	8,600,000	9,000,000	25,800,000	26,900,000
Expected return on plan assets	(8,600,000)	(8,800,000)	(25,900,000)	(26,400,000)
Amortization of actuarial loss	2,500,000	1,500,000	7,400,000	4,500,000
Net periodic benefit cost (income)	5,600,000	4,500,000	16,600,000	13,500,000
Benefit obligation and fair value of plan assets by pension plans
Consolidated pension funding contributions for 2012	9,200,000		9,200,000		20,000,000
Retiree Medical
Net periodic benefit cost and other amounts recognized in accumulated other comprehensive loss:
Service cost for benefits earned during the period	700,000	700,000	2,200,000	2,000,000
Interest cost on projected benefit obligation	900,000	1,100,000	2,700,000	3,200,000
Curtailment gain	(10,900,000)		(10,900,000)
Amortization of transition obligation	100,000	100,000	300,000	300,000
Amortization of actuarial loss	100,000	200,000	500,000	700,000
Net periodic benefit cost (income)	(9,100,000)	2,100,000	(5,200,000)	6,200,000
Reduction in certain retiree medical benefits	24,300,000
Reduction in certain retiree medical benefits recognized in other comprehensive income	13,400,000
Reduction in certain retiree medical benefits recognized in net periodic benefit plan cost recorded in cost of sales	9,600,000
Reduction in certain retiree medical benefits recognized in net periodic benefit plan cost recorded in selling, general and administrative expense	$ 1,300,000