Commitments and Contingencies - Annual Required Payments (Details) - USD ($)	9 Months Ended
	Apr. 30, 2016	Jun. 09, 2016
Minimum commitments under noncancelable operating leases
Remaining fiscal year	$ 1,422,000
2017	5,163,000
2018	3,918,000
2019	3,055,000
2020	2,026,000
Thereafter	4,553,000
Total	20,137,000
Total contractual obligations
Remaining fiscal year	3,637,000
2017	16,907,000
2018	7,672,000
2019	137,580,000
2020	2,914,000
Thereafter	6,276,000
Total	174,986,000
Jet Prep Ltd.
Total contractual obligations
Contingent consideration	148,000
Assumed contingent obligation	1,138,000
Cantel Medical (UK)
Total contractual obligations
Contingent guaranteed obligation	569,000
Compensation agreements
Other commitments
Remaining fiscal year	1,350,000
2017	8,562,000
2018	616,000
2019	498,000
2020	498,000
Thereafter	961,000
Total	12,485,000
Contingent consideration
Other commitments
2019	36,000
2020	132,000
Thereafter	40,000
Total	208,000
Contingent consideration | Jet Prep Ltd.
Total contractual obligations
Contingent consideration	$ 148,000
Discount rate of potential payments (as a percent)	12.60%
Assumed contingent liability
Other commitments
Remaining fiscal year	$ 1,000
2017	19,000
2018	93,000
2019	188,000
2020	246,000
Thereafter	719,000
Total	$ 1,266,000
Assumed contingent liability | Jet Prep Ltd.
Total contractual obligations
Discount rate of potential payments (as a percent)	2.50%
Assumed contingent obligation	$ 1,138,000
Contingent guaranteed obligation
Other commitments
Remaining fiscal year	90,000
2017	197,000
2018	147,000
2019	135,000
Total	$ 569,000
Contingent guaranteed obligation | Cantel Medical (UK)
Total contractual obligations
Discount rate of potential payments (as a percent)	10.10%
Contingent guaranteed obligation	$ 569,000
Other long-term obligations
Other commitments
Remaining fiscal year	101,000
2017	273,000
2018	205,000
2019	98,000
2020	12,000
Thereafter	3,000
Total	692,000
Credit Agreement
Maturity of the credit facility
2019	132,000,000
Total	132,000,000	$ 128,500,000
Expected interest payments under the credit facility
Remaining fiscal year	673,000
2017	2,693,000
2018	2,693,000
2019	1,570,000
Total	$ 7,629,000
Total contractual obligations
Weighted average interest rate on outstanding borrowings (as a percent)	2.04%