Goodwill and intangible assets (Tables)

6 Months Ended

Jan. 31, 2020

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		—		(291	)		(291	)
Foreign currency translation		94		(83	)		11
January 31, 2020	$	27,332	$	(26,580	)	$	752

Schedule of Intangible Assets [Table Text Block]

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

	January 31, 2020							July 31, 2019
	Gross		Accumulated Amortization			Net		Gross		Accumulated Amortization			Net
Patents	$	11,027	$	(11,005	)	$	22	$	11,027	$	(10,996	)	$	31
Customer relationships		11,840		(11,110	)		730		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	$	27,332	$	(26,580	)	$	752	$	27,238	$	(26,206	)	$	1,032

Schedule of Useful Lives For Acquisitions [Table Text Block]

At January 31, 2020, 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