Goodwill and intangible assets (Tables)

6 Months Ended

Jan. 31, 2019

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Indefinite-Lived Intangible Assets [Table Text Block]

The Company’s change in the carrying amount of intangible assets, all in the Products segment is as follows:

	Gross			Accumulated Amortization			Net
July 31, 2018	$	27,347		$	(25,461	)	$	1,886
Amortization expense		—			(494	)		(494	)
Foreign currency translation		(41	)		37			(4	)
January 31, 2019	$	27,306		$	(25,918	)	$	1,388

Schedule of Intangible Assets [Table Text Block]

Intangible assets, all finite lived, consist of the following:

	January 31, 2019							July 31, 2018
	Gross		Accumulated Amortization			Net		Gross		Accumulated Amortization			Net
Patents	$	11,027	$	(10,987	)	$	40	$	11,027	$	(10,980	)	$	47
Customer relationships		11,814		(10,466	)		1,348		11,836		(9,997	)		1,839
Website and acquired content		1,008		(1,008	)		—		1,008		(1,008	)		—
Licensed technology and other		483		(483	)		—		483		(483	)		—
Trademarks		2,974		(2,974	)		—		2,993		(2,993	)		—
Total	$	27,306	$	(25,918	)	$	1,388	$	27,347	$	(25,461	)	$	1,886

Schedule of Useful Lives For Acquisitions [Table Text Block]

At January 31, 2019, information with respect to intangibles assets acquired is as follows:

	Useful life assigned	Weighted average remaining useful life
Customer relationships	8 -15 years	2 years
Other intangibles	10 years	4 years