Employee Benefit Plans UK Pension Assets, Fair Value Measurement by Input Level (Details) - Pension Benefits, Non U.S. Plans - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Plans and Other Postretirement Benefit Plans
Diversified Growth Assets	$ 140.1	$ 156.3
Fixed Interest and Index-linked Securities	87.4	67.5
Cash Equivalents	0.9	7.7
Fair Value of Plan Assets	228.4	231.5	$ 246.3
Fair Value, Inputs, Level 1
Defined Benefit Plans and Other Postretirement Benefit Plans
Diversified Growth Assets	0.0	0.0
Fixed Interest and Index-linked Securities	79.9	62.2
Cash Equivalents	0.9	7.7
Fair Value of Plan Assets	80.8	69.9
Fair Value, Inputs, Level 2
Defined Benefit Plans and Other Postretirement Benefit Plans
Diversified Growth Assets	0.0	0.0
Fixed Interest and Index-linked Securities	0.0	0.0
Cash Equivalents	0.0	0.0
Fair Value of Plan Assets	0.0	0.0
Fair Value, Inputs, Level 3
Defined Benefit Plans and Other Postretirement Benefit Plans
Diversified Growth Assets	0.0	0.0
Fixed Interest and Index-linked Securities	0.0	0.0
Cash Equivalents	0.0	0.0
Fair Value of Plan Assets	0.0	0.0
NAV as a Practical Expedient
Defined Benefit Plans and Other Postretirement Benefit Plans
Diversified Growth Assets	140.1	156.3
Fixed Interest and Index-linked Securities	7.5	5.3
Cash Equivalents	0.0	0.0
Fair Value of Plan Assets	$ 147.6	$ 161.6

Diversified Growth Assets

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Amount of short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

+ 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 210.5-02.1)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash Equivalents
-URI http://asc.fasb.org/extlink&oid=6507016

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Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 30
-Section 35
-Paragraph 50
-URI http://asc.fasb.org/extlink&oid=64937038&loc=d3e12355-114930

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Plan Assets
-URI http://asc.fasb.org/extlink&oid=6749337

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Plan Assets
-URI http://asc.fasb.org/extlink&oid=6520858

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+ References

No definition available.

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For an unclassified balance sheet, this item represents investments in debt securities having predetermined or determinable maturity dates.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1(a))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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