Revenue (Disaggregation of Revenue) (Details) - USD ($) $ in Thousands	3 Months Ended
	Oct. 31, 2020	Oct. 31, 2019
Disaggregation of Revenue [Line Items]
Total revenue	$ 169,802	$ 157,010
United States
Disaggregation of Revenue [Line Items]
Total revenue	112,350	98,441
Canada
Disaggregation of Revenue [Line Items]
Total revenue	19,032	14,785
Other Americas
Disaggregation of Revenue [Line Items]
Total revenue	3,194	3,488
Total Americas
Disaggregation of Revenue [Line Items]
Total revenue	134,576	116,714
United Kingdom
Disaggregation of Revenue [Line Items]
Total revenue	11,644	9,934
Other EMEA
Disaggregation of Revenue [Line Items]
Total revenue	12,901	11,116
Total EMEA
Disaggregation of Revenue [Line Items]
Total revenue	24,545	21,050
Total APAC
Disaggregation of Revenue [Line Items]
Total revenue	10,681	19,246
Subscription and support
Disaggregation of Revenue [Line Items]
Total revenue	57,966	49,031
Subscription and support | United States
Disaggregation of Revenue [Line Items]
Total revenue	39,013	33,646
Subscription and support | Canada
Disaggregation of Revenue [Line Items]
Total revenue	7,142	4,545
Subscription and support | Other Americas
Disaggregation of Revenue [Line Items]
Total revenue	1,113	1,085
Subscription and support | Total Americas
Disaggregation of Revenue [Line Items]
Total revenue	47,268	39,276
Subscription and support | United Kingdom
Disaggregation of Revenue [Line Items]
Total revenue	2,030	2,080
Subscription and support | Other EMEA
Disaggregation of Revenue [Line Items]
Total revenue	5,120	4,341
Subscription and support | Total EMEA
Disaggregation of Revenue [Line Items]
Total revenue	7,150	6,421
Subscription and support | Total APAC
Disaggregation of Revenue [Line Items]
Total revenue	3,548	3,334
Subscription
Disaggregation of Revenue [Line Items]
Total revenue	37,230	28,060
Support
Disaggregation of Revenue [Line Items]
Total revenue	20,736	20,971
License
Disaggregation of Revenue [Line Items]
Total revenue	65,283	54,363
License | United States
Disaggregation of Revenue [Line Items]
Total revenue	40,977	27,467
License | Canada
Disaggregation of Revenue [Line Items]
Total revenue	10,753	8,990
License | Other Americas
Disaggregation of Revenue [Line Items]
Total revenue	235	234
License | Total Americas
Disaggregation of Revenue [Line Items]
Total revenue	51,965	36,691
License | United Kingdom
Disaggregation of Revenue [Line Items]
Total revenue	8,299	5,540
License | Other EMEA
Disaggregation of Revenue [Line Items]
Total revenue	803	726
License | Total EMEA
Disaggregation of Revenue [Line Items]
Total revenue	9,102	6,266
License | Total APAC
Disaggregation of Revenue [Line Items]
Total revenue	4,216	11,406
Term license
Disaggregation of Revenue [Line Items]
Total revenue	65,225	54,314
Perpetual license
Disaggregation of Revenue [Line Items]
Total revenue	58	49
Services
Disaggregation of Revenue [Line Items]
Total revenue	46,553	53,616
Services | United States
Disaggregation of Revenue [Line Items]
Total revenue	32,360	37,328
Services | Canada
Disaggregation of Revenue [Line Items]
Total revenue	1,137	1,250
Services | Other Americas
Disaggregation of Revenue [Line Items]
Total revenue	1,846	2,169
Services | Total Americas
Disaggregation of Revenue [Line Items]
Total revenue	35,343	40,747
Services | United Kingdom
Disaggregation of Revenue [Line Items]
Total revenue	1,315	2,314
Services | Other EMEA
Disaggregation of Revenue [Line Items]
Total revenue	6,978	6,049
Services | Total EMEA
Disaggregation of Revenue [Line Items]
Total revenue	8,293	8,363
Services | Total APAC
Disaggregation of Revenue [Line Items]
Total revenue	$ 2,917	$ 4,506