Segment Reporting (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Revenue	$ 3,499.1	$ 3,469.2
Americas
Revenue	2,198.5	2,151.0
Long-lived assets and goodwill	6,435.2	6,136.3
UNITED STATES
Revenue	2,007.6	1,958.2
EMEA
Revenue	946.3	961.4
Long-lived assets and goodwill	2,756.5	2,635.6
Asia Pacific
Revenue	354.3	356.8
Long-lived assets and goodwill	$ 542.6	$ 549.4

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration