Income Taxes - Narrative (Details) - USD ($) $ in Millions	9 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Sep. 30, 2019
Income Tax Disclosure [Abstract]
Effective tax rate, percent	25.90%	30.30%
CARES Act impact	$ 5.1
Transition tax			$ 0.7

Coronavirus Aid, Relief and Economic Security Act, Unfavorable Impact

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- Definition

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319

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- References

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- Definition

Amount of tax liability from transition tax on accumulated earnings of controlled foreign corporation deemed repatriated pursuant to Tax Cuts and Jobs Act, classified as noncurrent.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-URI http://asc.fasb.org/topic&trid=2144680

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