Employee Benefit Plans (Tables)
 9 Months Ended
Apr. 30, 2019
Retirement Benefits, Description [Abstract]  
Components of net periodic pension costs
Net periodic benefit costs for the Company’s pension plans include the following components (in millions):
 
Three Months Ended
April 30,
 
Nine Months Ended
April 30,
 
2019

 
2018

 
2019

 
2018

Net periodic benefit costs:
 

 
 

 
 

 
 

Service cost
$
1.5

 
$
2.1

 
$
4.5

 
$
6.2

Interest cost
4.1

 
3.8

 
12.3

 
11.2

Expected return on assets
(6.6
)
 
(6.6
)
 
(19.9
)
 
(19.7
)
Prior service cost amortization
0.1

 
—

 
0.4

 
0.3

Actuarial loss amortization
1.1

 
1.2

 
3.3

 
3.5

Net periodic benefit costs
$
0.2

 
$
0.5

 
$
0.6

 
$
1.5