Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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

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The charge against earnings resulting from the aggregate write down of tangible assets from their carrying value to their fair value.

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Description of Business and Summary of Significant Accounting Policies - Impairment Charges (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease, impairment loss		$ 3.6	$ 15.2	$ 3.6	$ 15.3
Fixed asset impairment charges			$ 2.9		$ 2.9
Marketing Services
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Impairments	$ 16.4
SaaS
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Impairments	$ 1.8