Employee Benefit Plans (Detail) - USD ($) $ in Millions |
12 Months Ended | |
|---|---|---|
Sep. 30, 2020 |
Sep. 30, 2019 |
|
| Retirement Benefits [Abstract] | ||
| Defined contribution costs | $ 3.4 | $ 2.9 |
| X | ||||||||||
- References No definition available.
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| X | ||||||||||
- Definition Amount of cost for defined contribution plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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