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Discontinued Operations, Goodwill, and Intangible Assets - Segments (Details) $ in Thousands	12 Months Ended
	Sep. 30, 2020 USD ($)
Changes in the carrying value of goodwill by reporting segment
Goodwill at the beginning of the period	$ 3,476,813
Foreign Exchange Impact	7,400
Goodwill at the end of the period	3,484,221
Americas
Changes in the carrying value of goodwill by reporting segment
Goodwill at the beginning of the period	2,618,600
Foreign Exchange Impact	(1,500)
Goodwill at the end of the period	2,617,100
International
Changes in the carrying value of goodwill by reporting segment
Goodwill at the beginning of the period	858,200
Foreign Exchange Impact	8,900
Goodwill at the end of the period	$ 867,100

X

- 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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(10)(1))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=120320667&loc=SL49117168-202975

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266

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X

- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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