Restructuring Charges - Restructuring Reserve Activity (Details) - USD ($)	3 Months Ended		9 Months Ended	12 Months Ended
	Oct. 30, 2015	Jul. 31, 2015	Jul. 31, 2015	Oct. 30, 2015
Employee Severance
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Expected Cost		$ 19,550,000	$ 19,550,000
Restructuring Reserve [Roll Forward]
Beginning accrual	$ 9,022,000	9,328,000	0	$ 0
Costs incurred		7,775,000	19,550,000
Costs paid/settled		(7,963,000)	(10,528,000)
Effect of foreign currency translation		(118,000)	0
Ending accrual		9,022,000	9,022,000
Scenario, Forecast [Member]
Restructuring Cost and Reserve [Line Items]
Other Restructuring Costs	2,300,000			9,400,000.0
Restructuring and Related Cost, Accelerated Depreciation				6,300,000
Severance Costs	4,000,000.0			24,000,000.0
Minimum | Scenario, Forecast [Member]
Restructuring Reserve [Roll Forward]
Costs incurred	10,000,000			30,000,000
Maximum | Scenario, Forecast [Member]
Restructuring Reserve [Roll Forward]
Costs incurred	$ 20,000,000			$ 40,000,000
Underground Mining Machinery [Member] | Employee Severance
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Expected Cost		12,312,000	12,312,000
Restructuring Reserve [Roll Forward]
Costs incurred		6,896,000	12,312,000
Surface Mining Equipment [Member] | Employee Severance
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Expected Cost		6,986,000	6,986,000
Restructuring Reserve [Roll Forward]
Costs incurred		879,000	6,986,000
Corporate Segment [Member] | Employee Severance
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Expected Cost		252,000	252,000
Restructuring Reserve [Roll Forward]
Costs incurred		$ 0	$ 252,000