Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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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 of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

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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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Goodwill and Intangible Assets - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Finite-Lived Intangible Assets [Line Items]
Impairments	$ 16.4	$ 0.0
Amortization of acquired intangibles	1.6
Customer Relationships
Finite-Lived Intangible Assets [Line Items]
Additions	0.0	0.0
Customer Relationships \| Minimum
Finite-Lived Intangible Assets [Line Items]
Acquired infinite-lived intangible asset, useful life			3 years
Customer Relationships \| Maximum
Finite-Lived Intangible Assets [Line Items]
Acquired infinite-lived intangible asset, useful life			10 years
Trade Names
Finite-Lived Intangible Assets [Line Items]
Additions	1.0	1.0
Liquid Alpha
Finite-Lived Intangible Assets [Line Items]
Impairments	$ 16.4	$ 0.0