Restructuring and Separation Costs - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2020
Restructuring Cost And Reserve [Line Items]
Commencement of chapter 11 cases in bankruptcy court , date of petition filed		Apr. 26, 2020
Restructuring and Separation Costs [Member]
Restructuring Cost And Reserve [Line Items]
Legal and other professional advisor fees incurred prior to petition date		$ 7.4
Severance and related costs	$ 0.4	$ 10.1

Date petition for bankruptcy filed with the bankruptcy court, in CCYY-MM-DD format.

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Discloses the amount charged against the accrued restructuring reserves, or earnings if not previously accrued, during the period for the specified type of restructuring cost.

+ References

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Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

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