Employee Benefit Plans (Details) - USD ($) $ in Millions |
12 Months Ended | ||
---|---|---|---|
Sep. 30, 2018 |
Sep. 30, 2017 |
Sep. 30, 2016 |
|
Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Abstract] | |||
Contributions by the Company to the plan | $ 10.5 | $ 10.5 | $ 9.5 |
Employer contribution, vesting period | 4 years |