Amount of costs incurred to date for the specified restructuring cost.

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The expected number of positions to be eliminated as a result of restructuring activities.

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The number of positions eliminated during the period as a percentage of total positions eliminated during the period in connection with the restructuring plan(s).

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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.

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Amount, after cash payment, of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Restructuring Activities - Additional Information (Details)	3 Months Ended	12 Months Ended
	Sep. 30, 2020 Employee	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Restructuring Cost And Reserve [Line Items]
Restructuring related expenses		$ 1,176,000	$ 497,000
Unpaid remained associated cost amount		$ 0
2019 Restructuring Plan [Member]
Restructuring Cost And Reserve [Line Items]
Percentage headcount reduction		6.00%
2018 Restructuring Plan [Member]
Restructuring Cost And Reserve [Line Items]
Percentage headcount reduction		13.00%
Restructuring and Reduction in Force Plan [Member] \| 2020 Restructuring Plan [Member]
Restructuring Cost And Reserve [Line Items]
Expected reduction of workforce \| Employee	60