Special Charges and Other - General Information (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021 USD ($)	Sep. 30, 2021 USD ($)
Restructuring Charges
Restructuring charges	$ (133)	$ (250)
Asset Impairment Charges
Impairment	2,047	3,269
Investments	8,500	8,500
Impairment on investments		5,100
Employee severance and termination benefits
Restructuring Charges
Restructuring charges	(357)	(557)
Lease shutdown costs
Restructuring Charges
Restructuring charges	$ 224	307
Transformation Initiative, 2020
Asset Impairment Charges
Impairment		2,800
Transformation Initiative, 2020 \| Employee severance and termination benefits
Restructuring Charges
Restructuring charges		600
Transformation Initiative, 2020 \| Lease shutdown costs
Restructuring Charges
Restructuring charges		$ 300

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount of investment in equity security without readily determinable fair value.

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Amount 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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