Goodwill and intangible assets (Tables)

3 Months Ended

Oct. 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, 2019	$	27,238	$	(26,206	)	$	1,032
Amortization expense		—		(723	)		(723	)
Foreign currency translation		51		532			583
October 31, 2019	$	27,289	$	(26,397	)	$	892

Schedule of Intangible Assets [Table Text Block]

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

	October 31, 2019							July 31, 2019
	Gross		Accumulated Amortization			Net		Gross		Accumulated Amortization			Net
Patents	$	11,026	$	(11,000	)	$	26	$	11,027	$	(10,996	)	$	31
Customer relationships		11,798		(10,932	)		866		11,746		(10,745	)		1,001
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	)		—		2,974		(2,974	)		—
Total	$	27,289	$	(26,397	)	$	892	$	27,238	$	(26,206	)	$	1,032

Schedule of Useful Lives For Acquisitions [Table Text Block]

At October 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	1 year
Other intangibles	10 years	3 years