Income Taxes - Provision (Benefit) (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Income Tax Expense (Benefit), Continuing Operations [Abstract]
Income tax (benefit) provision	$ 2,963	$ 5,830
Reduction in deferred tax liabilities related to extension of tax rate in china	(500)
Benefit related to stock compensation windfalls	$ 5,800	3,700
Benefit related to remeasurement of net U.S. deferred tax assets		1,400
Transition tax reduction		$ 1,100

Income Tax Expense (Benefit), Increase (Decrease), Remeasurement of Net Domestic Deferred Tax Assets

No definition available.

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- Definition

Income Tax Expense (Benefit), Increase (Decrease), Stock Compensation Discrete Expense (Benefit)

+ References

No definition available.

+ Details

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- Definition

Amount 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 280
-SubTopic 10
-Section 50
-Paragraph 22
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(h))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 20
-Section 45
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109238882&loc=d3e38679-109324

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- References

No definition available.

+ Details

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- Definition

Amount of increase (decrease) in deferred obligations classified as other.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

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- Definition

Amount of decrease in deferred tax liability previously recognized attributable to taxable temporary differences from undistributed earnings of foreign subsidiary and other recognized entity now subject to transition tax.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32621-109319

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