Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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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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- References

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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-Section 50
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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 after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 210
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-Section S99
-Paragraph 1
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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

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Summary of Significant Accounting Policies, Property, Plant and Equipment (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Property and Equipment [Abstract]
Depreciation expense	$ 169.3	$ 157.6	$ 156.5
Property, Plant and Equipment [Line Items]
Property and equipment, gross value	1,470.1	1,362.6
Total accumulated depreciation	(806.2)	(660.7)
Net property and equipment	663.9	701.9
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross value	$ 127.9	115.4
Furniture and Fixtures [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Depreciable life	3 years
Furniture and Fixtures [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Depreciable life	13 years
Computer equipment and software [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross value	$ 829.8	752.9
Computer equipment and software [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Depreciable life	3 years
Computer equipment and software [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Depreciable life	10 years
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross value	$ 352.4	308.6
Leasehold Improvements [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Depreciable life	1 year
Leasehold Improvements [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Depreciable life	10 years
Automobiles [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross value	$ 160.0	$ 185.7
Automobiles [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Depreciable life	2 years
Automobiles [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Depreciable life	30 years