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Investments - Other Investments (Details) - USD ($) $ in Millions		3 Months Ended
	Jul. 26, 2016	Mar. 31, 2017	Mar. 31, 2016
Equity Method Investment, Aggregate Cost [Roll Forward]
Opening undistributed value of investment		$ 12.1	$ 9.5
Initial investment		2.3
Proceeds from Sale of Equity Method Investments		(9.3)	0.0
Equity Method Investment, Unrealized Intercompany Profit (Loss) Not Eliminated, Amount		1.7
Closing value of investment		5.0	9.5
Goodwill, Acquired During Period		1.8	22.1
MVI
Equity Method Investment, Aggregate Cost [Roll Forward]
Opening undistributed value of investment		0.5	0.8
Initial investment		0.0
Proceeds from Sale of Equity Method Investments		0.0
Equity Method Investment, Unrealized Intercompany Profit (Loss) Not Eliminated, Amount		0.0
Closing value of investment		0.5	0.8
Goodwill, Acquired During Period		0.0
Chaspark
Equity Method Investment, Aggregate Cost [Roll Forward]
Opening undistributed value of investment		8.4	8.7
Initial investment		0.0
Proceeds from Sale of Equity Method Investments		(9.3)
Equity Method Investment, Unrealized Intercompany Profit (Loss) Not Eliminated, Amount		1.7
Closing value of investment		0.8	$ 8.7
Goodwill, Acquired During Period		0.0
Bene
Equity Method Investment, Aggregate Cost [Roll Forward]
Opening undistributed value of investment		3.2
Initial investment	$ 3.3	0.0
Proceeds from Sale of Equity Method Investments		0.0
Equity Method Investment, Unrealized Intercompany Profit (Loss) Not Eliminated, Amount		0.0
Closing value of investment		3.2
Goodwill, Acquired During Period		0.0
Digital Re
Equity Method Investment, Aggregate Cost [Roll Forward]
Opening undistributed value of investment		0.0
Initial investment		2.3
Proceeds from Sale of Equity Method Investments		0.0
Equity Method Investment, Unrealized Intercompany Profit (Loss) Not Eliminated, Amount		0.0
Closing value of investment		0.5
Goodwill, Acquired During Period		$ 1.8

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Equity Method Investment, Aggregate Cost [Roll Forward]

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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-Publisher FASB
-Name Accounting Standards Codification
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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.

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-Publisher FASB
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The cash inflow associated with the sale of equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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