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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
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-Section 50
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Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-SubTopic 10
-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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.13)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher SEC
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-Section 02
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Other Financial Information, Property and Equipment (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Property and Equipment [Line Items]
Property and equipment, gross	$ 1,976.2	$ 1,730.2
Construction-in-process, gross	158.2	70.3
Accumulated depreciation	(955.2)	(825.9)
Property and equipment, net	1,021.0	904.3
Depreciation expense	141.5	141.9	$ 148.2
Construction in Progress [Member]
Property and Equipment [Line Items]
Property and equipment, net	45.6
Computers and equipment [Member]
Property and Equipment [Line Items]
Property and equipment, gross	915.1	806.1
Software [Member]
Property and Equipment [Line Items]
Property and equipment, gross	169.1	161.2
Leasehold Improvements [Member]
Property and Equipment [Line Items]
Property and equipment, gross	203.4	179.5
Furniture and fixtures [Member]
Property and Equipment [Line Items]
Property and equipment, gross	43.2	33.7
Building and Building Improvements [Member]
Property and Equipment [Line Items]
Property and equipment, gross	246.1	238.4
Land and land improvements [Member]
Property and Equipment [Line Items]
Property and equipment, gross	$ 241.1	$ 241.0