Intangibles and Goodwill - Intangible Assets Summary (Details) - USD ($)	3 Months Ended		9 Months Ended
	Apr. 30, 2017	Apr. 30, 2016	Apr. 30, 2017	Apr. 30, 2016	Jul. 31, 2016
Intangible assets with finite lives:
Amortization expense	$ 3,964,000	$ 3,346,000	$ 11,930,000	$ 9,737,000
Gross	173,519,000		173,519,000		$ 145,210,000
Accumulated Amortization	(52,857,000)		(52,857,000)		(41,002,000)
Net	120,662,000		120,662,000		104,208,000
Intangible assets with indefinite lives:
Trademarks and tradenames	7,477,000		7,477,000		7,511,000
Total intangible assets
Gross	180,996,000		180,996,000		152,721,000
Accumulated Amortization	(52,857,000)		(52,857,000)		(41,002,000)
Net	128,139,000		$ 128,139,000		111,719,000
Minimum
Intangible assets with finite lives:
Estimated useful lives			3 years
Maximum
Intangible assets with finite lives:
Estimated useful lives			20 years
Weighted average
Intangible assets with finite lives:
Estimated useful lives			12 years
Customer relationships
Intangible assets with finite lives:
Gross	116,893,000		$ 116,893,000		100,649,000
Accumulated Amortization	(32,017,000)		(32,017,000)		(24,689,000)
Net	84,876,000		84,876,000		75,960,000
Total intangible assets
Accumulated Amortization	(32,017,000)		(32,017,000)		(24,689,000)
Technology
Intangible assets with finite lives:
Gross	42,543,000		42,543,000		32,767,000
Accumulated Amortization	(15,416,000)		(15,416,000)		(11,813,000)
Net	27,127,000		27,127,000		20,954,000
Total intangible assets
Accumulated Amortization	(15,416,000)		(15,416,000)		(11,813,000)
Brand names
Intangible assets with finite lives:
Gross	8,163,000		8,163,000		6,194,000
Accumulated Amortization	(3,024,000)		(3,024,000)		(2,394,000)
Net	5,139,000		5,139,000		3,800,000
Total intangible assets
Accumulated Amortization	(3,024,000)		(3,024,000)		(2,394,000)
Non-compete agreements
Intangible assets with finite lives:
Gross	3,092,000		3,092,000		3,092,000
Accumulated Amortization	(1,370,000)		(1,370,000)		(1,193,000)
Net	1,722,000		1,722,000		1,899,000
Total intangible assets
Accumulated Amortization	(1,370,000)		(1,370,000)		(1,193,000)
Patents and other registrations
Intangible assets with finite lives:
Gross	2,828,000		2,828,000		2,508,000
Accumulated Amortization	(1,030,000)		(1,030,000)		(913,000)
Net	1,798,000		1,798,000		1,595,000
Total intangible assets
Accumulated Amortization	$ (1,030,000)		$ (1,030,000)		$ (913,000)