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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The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale.

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Amount of loss from impairment of right-of-use asset from operating lease.

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Description of Business and Summary of Significant Accounting Policies - Impairment Charges (Details) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended		9 Months Ended
	Jul. 31, 2020	Jun. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease, impairment charges	$ 1,200		$ 0		$ 3,600	$ 16,500
Fixed asset impairment charges						2,900
Impairment charges			$ 0	$ 1,184	$ 3,611	$ 19,414
Marketing Services
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease, impairment charges	1,000
Impairment charges		$ 16,400
SaaS
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease, impairment charges	$ 200
Impairment charges		$ 1,800