Intangible Assets (Details) - USD ($)	3 Months Ended		12 Months Ended
	Oct. 31, 2016	Oct. 31, 2015	Jul. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	$ 361,095,000		$ 361,095,000
Accumulated amortization	82,456,000		76,401,000
Net carrying amount	278,639,000		$ 284,694,000
Amortization of intangibles	6,055,000	$ 1,376,000
Amortization expense - year one	22,823,000
Amortization expense - year two	21,075,000
Amortization expense - year three	17,155,000
Amortization expense - year four	17,155,000
Amortization expense - year five	$ 16,196,000
Customer Relationships
Finite-Lived Intangible Assets [Line Items]
Weighted average amortization period	20 years 3 months 18 days		20 years 3 months 18 days
Gross carrying amount	$ 249,831,000		$ 249,831,000
Accumulated amortization	31,865,000		28,497,000
Net carrying amount	$ 217,966,000		$ 221,334,000
Technologies
Finite-Lived Intangible Assets [Line Items]
Weighted average amortization period	12 years 3 months 18 days		12 years 3 months 18 days
Gross carrying amount	$ 82,370,000		$ 82,370,000
Accumulated amortization	44,300,000		42,860,000
Net carrying amount	$ 38,070,000		$ 39,510,000
Trademarks and other
Finite-Lived Intangible Assets [Line Items]
Weighted average amortization period	16 years 3 months 18 days		16 years 3 months 18 days
Gross carrying amount	$ 28,894,000		$ 28,894,000
Accumulated amortization	6,291,000		5,044,000
Net carrying amount	$ 22,603,000		$ 23,850,000