Fair Value Measurements - Schedule of Contingent Consideration Liability (Detail) - Contingent Consideration [Member] - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2019	Sep. 30, 2018
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Contingent consideration liability, beginning balance	$ 14,466	$ 14,864
Fair value adjustments	(415)	288
Settlements	(10,979)	(925)
Interest accretion	254	387
Foreign currency translation	(126)	(148)
Contingent consideration liability, ending balance	$ 3,200	$ 14,466

Fair value measurement with unobservable inputs reconciliation recurring basis liability foreign currency translation.

No definition available.

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- Definition

Fair value measurement with unobservable inputs reconciliation recurring basis liability interest accretion.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

Amount of settlements of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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