Warranty (Tables)
 9 Months Ended
Apr. 30, 2019
Standard Product Warranty Disclosure [Abstract]  
Reconciliation of warranty reserves
The following is a reconciliation of warranty reserves, included in other current liabilities and other long-term liabilities, for the nine months ended April 30, 2019 and 2018 (in millions):
 
Nine Months Ended
April 30,
 
2019

 
2018

Balance at beginning of period
$
18.9

 
$
14.6

Accruals for warranties issued during the reporting period
1.6

 
1.8

Accruals related to pre-existing warranties (including changes in estimates)
(2.0
)
 
0.6

Less: settlements made during the period
(6.9
)
 
(3.3
)
Balance at end of period
$
11.6

 
$
13.7