Income Taxes (Tables)
 3 Months Ended
Mar. 31, 2018
Income Tax Disclosure [Abstract]  
Schedule of Income tax provision and the respective effective income tax rates Our income tax provision for the periods presented and the respective effective income tax rates for such periods are as follows (in millions, except for income tax rates): 
 
 
For the Three Months Ended
 
 
March 31,
 
 
2018
 
2017
Income tax provision
 
$
7.3

 
$
5.0

 
 
 
 
 
Effective income tax rate
 
19.0
%
 
13.9
%