Stockholders' Equity - Non-cash compensation expense (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Stockholders' Equity
Non-cash compensation expense related to stock-based awards	$ 4,477	$ 2,720
Estimated forfeiture rate (as a percent)	12.50%
Cost of sales
Stockholders' Equity
Non-cash compensation expense related to stock-based awards	$ 539	313
Selling, general and administrative
Stockholders' Equity
Non-cash compensation expense related to stock-based awards	3,938	$ 2,407
RSUs
Stockholders' Equity
Unrecognized compensation cost related to unvested awards	61,500
Aggregate fair value of awards	$ 57,600
Weighted-average period of recognition	1 year 6 months

Represents the estimated forfeiture rate of share-based compensation awards.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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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