Stock-based compensation - Summary of shares available for grant activity (Details) - shares shares in Thousands	3 Months Ended	5 Months Ended
Sep. 30, 2020	Nov. 20, 2019
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant [Roll Forward]
Shares available for grant (in shares)	5,280
Additional shares authorized (in shares)	84
Granted (in shares)	(575)
RSUs withheld for taxes in net share settlements (in shares)	5	5
Canceled (in shares)	2	2
Shares available for grant (in shares)	4,796

Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant [Roll Forward]

No definition available.

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ 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
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

Number of additional shares authorized for issuance under share-based payment arrangement.

+ References

No definition available.

+ Details

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ 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
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

+ Details

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- Definition

Other than shares newly issued, the number of additional shares issued (for example, a stock split) or canceled (for example, to correct a share issuance), during the period under the plan.

+ References

+ Details

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- Definition

Number of shares used to settle grantee's tax withholding obligation for award under share-based payment arrangement.

+ References

No definition available.

+ Details

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