The amount of identifiable intangible assets recognized as of the acquisition date.

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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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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

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Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

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Goodwill and Intangible Assets - Narrative (Details) - USD ($) $ in Millions		1 Months Ended	3 Months Ended	12 Months Ended
	Oct. 01, 2020	Oct. 31, 2021	Jun. 30, 2019	Dec. 31, 2021	Dec. 31, 2019
Goodwill
Goodwill impairment				$ 0.0
Impairment of infinite lived intangible assets				0.0
Trade names
Goodwill
Impairment of infinite lived intangible assets				0.0
BCG
Goodwill
Goodwill impairment	$ 5.6	$ 5.6
Acquired finite-lived intangible assets					$ 14.1
Impairment of finite lived intangible assets	3.6
BCG \| Trade names
Goodwill
Impairment of infinite lived intangible assets	$ 0.8
NTA
Goodwill
Acquired finite-lived intangible assets					$ 160.4
Retirement
Goodwill
Goodwill impairment			$ 28.0	$ 0.0