Quarterly report pursuant to Section 13 or 15(d)

Income Tax (Details)

v3.8.0.1
Income Tax (Details) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Mar. 31, 2018
Dec. 31, 2017
Mar. 31, 2017
Mar. 31, 2018
Mar. 31, 2017
Income Tax Disclosure [Abstract]          
Tax cuts and jobs act of 2017, transition tax for accumulated foreign earnings income tax expense (benefit)   $ 9.5   $ 9.5  
Tax Cuts And Jobs Act Of 2017, incomplete accounting, change in tax rate, deferred tax liability, provisional income tax (expense) benefit $ 1.1     11.7  
Tax cuts and jobs act of 2017, income tax expense (benefit) $ 6.4 $ 6.4   $ 12.8  
Effective income tax rate, percent 24.10%   33.60% 24.50% 35.10%
Tax cuts and jobs act of 2017, income (decrease) in the effective income tax rate 1.50%     1.40%  
Income taxes paid       $ 28.5 $ 38.8