Goodwill and Other Intangible Assets (Goodwill) (Details) $ in Millions	3 Months Ended
Mar. 31, 2019 USD ($)
Goodwill [Roll Forward]
Balances	$ 9,346.8
Additions	0.0
Goodwill related to assets held for sale	0.0
Other	1.0
Currency translation adjustments	17.6
Balances	9,365.4
Application Software
Goodwill [Roll Forward]
Balances	5,236.1
Additions	0.0
Goodwill related to assets held for sale	0.0
Other	1.0
Currency translation adjustments	10.3
Balances	5,247.4
Network Software & Systems
Goodwill [Roll Forward]
Balances	2,623.7
Additions	0.0
Goodwill related to assets held for sale	0.0
Other	0.0
Currency translation adjustments	0.7
Balances	2,624.4
Measurement &Analytical Solutions
Goodwill [Roll Forward]
Balances	1,174.7
Additions	0.0
Goodwill related to assets held for sale	0.0
Other	0.0
Currency translation adjustments	4.7
Balances	1,179.4
Process Technologies
Goodwill [Roll Forward]
Balances	312.3
Additions	0.0
Goodwill related to assets held for sale	0.0
Other	0.0
Currency translation adjustments	1.9
Balances	$ 314.2

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-SubTopic 20
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 25
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e961-128460

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