Intangible Assets and Goodwill - Goodwill (Details) $ in Millions	6 Months Ended
Jun. 30, 2017 USD ($)
Changes in carrying amount of goodwill
Balance at the beginning of the period	$ 516.4
Acquisitions	264.6
Disposals	0.0
Other	8.8
Balance at the end of the period	789.8
Domestic Financial Services
Changes in carrying amount of goodwill
Balance at the beginning of the period	345.8
Acquisitions	68.7
Disposals	0.0
Other	0.4
Balance at the end of the period	414.9
International Financial Services
Changes in carrying amount of goodwill
Balance at the beginning of the period	15.6
Acquisitions	195.9
Disposals	0.0
Other	8.4
Balance at the end of the period	219.9
Healthcare Services
Changes in carrying amount of goodwill
Balance at the beginning of the period	155.0
Acquisitions	0.0
Disposals	0.0
Other	0.0
Balance at the end of the period	$ 155.0

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=64834752&loc=SL49117168-202975

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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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- Definition

Amount of increase (decrease), classified as other, of an asset representing the future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

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

+ References

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