Goodwill and intangible assets (Details) - Schedule of useful lives for acquisitions	6 Months Ended
	Jan. 31, 2015
Customer Relationships [Member] | Minimum [Member]
Goodwill and intangible assets (Details) - Schedule of useful lives for acquisitions [Line Items]
Useful life assigned	8 years
Customer Relationships [Member] | Maximum [Member]
Goodwill and intangible assets (Details) - Schedule of useful lives for acquisitions [Line Items]
Useful life assigned	15 years
Customer Relationships [Member]
Goodwill and intangible assets (Details) - Schedule of useful lives for acquisitions [Line Items]
Weighted average remaining useful life	5 years 6 months
Trademarks [Member]
Goodwill and intangible assets (Details) - Schedule of useful lives for acquisitions [Line Items]
Useful life assigned	5 years
Weighted average remaining useful life	2 years 6 months
Other Intangible Assets [Member] | Minimum [Member]
Goodwill and intangible assets (Details) - Schedule of useful lives for acquisitions [Line Items]
Useful life assigned	4 years
Other Intangible Assets [Member] | Maximum [Member]
Goodwill and intangible assets (Details) - Schedule of useful lives for acquisitions [Line Items]
Useful life assigned	5 years
Other Intangible Assets [Member]
Goodwill and intangible assets (Details) - Schedule of useful lives for acquisitions [Line Items]
Weighted average remaining useful life	6 months