Overview, Basis of Presentation and Significant Accounting Policies - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Depreciation expense	$ 1.4	$ 1.7
Real Estate Held for sale	5.5		$ 5.5
Equity investments carrying value	13.3		$ 13.4
Unrealized loss on investment	0.2
Computer Software, Intangible Asset
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Amortization expense related to internally-developed software	$ 8.2	$ 7.3
Maximum \| Computer Software, Intangible Asset
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Estimated useful life of computer software	3 years

Organization, consolidation and presentation of financial statements line items.

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- Definition

Amount of expense for amortization of capitalized computer software costs.

+ References

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- Definition

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

+ References

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- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of unrealized loss on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Carrying amount as of the balance sheet date of investments in land and buildings held for sale, excluding real estate considered to be inventory of the entity.

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