Goodwill (Details) - USD ($) $ in Millions	Mar. 31, 2022	Sep. 30, 2021
Goodwill [Abstract]
Goodwill, gross	$ 180.7	$ 180.7
Accumulated impairment losses	(114.8)	(114.8)
Goodwill	$ 65.9	$ 65.9

Goodwill [Abstract]

No definition available.

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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- Definition

Amount before accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- Definition

Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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