Quarterly report pursuant to Section 13 or 15(d)

Retirement Benefits - Narrative (Details)

v3.10.0.1
Retirement Benefits - Narrative (Details) - USD ($)
$ in Millions
3 Months Ended 9 Months Ended
Jun. 30, 2018
Dec. 31, 2017
Jun. 30, 2017
Jun. 30, 2018
Jun. 30, 2017
Retirement Benefits [Abstract]          
Pension Contributions   $ 80.0      
Postemployment Benefits, Period Expense $ 0.0   $ 0.1 $ 0.1 $ 0.3
Defined Contribution Plan, Cost $ 3.0   $ 2.7 $ 8.6 $ 8.4