Pension Plans and Other Postretirement Benefit Plans - Net Funded Status of Over-Funded, Underfunded, and Unfunded Pension Plans (Details) - USD ($) $ in Millions	Mar. 31, 2017	Dec. 31, 2016
Pension plans and other postretirement benefit plans
Overfunded defined benefit pension plans	$ 22.0	$ 21.2
Underfunded defined benefit pension plans	(86.2)	(83.2)
Pension Plans
Pension plans and other postretirement benefit plans
Overfunded defined benefit pension plans	22.0	21.2
Underfunded defined benefit pension plans	(86.2)	(83.2)
Pension liabilities included in other current liabilities	(0.5)	(0.4)
Net funded status	(64.7)	(62.4)
Underfunded defined benefit pension plans \| Pension Plans
Pension plans and other postretirement benefit plans
Underfunded defined benefit pension plans	(57.7)	(55.6)
Unfunded defined benefit pension plans \| Pension Plans
Pension plans and other postretirement benefit plans
Underfunded defined benefit pension plans	$ (28.5)	$ (27.6)

This represents the current liability recognized in the balance sheet that is associated with the defined benefit pension plans.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e2410-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.24)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e2417-114920

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
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Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Topic 715
-SubTopic 20
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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

This represents the noncurrent liability recognized in the balance sheet that is associated with the defined benefit pension plans.

+ References

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e2410-114920

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.24)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64852052&loc=d3e1703-114919

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e2417-114920

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- Definition

The amount for overfunded plans recognized in the balance sheet as a noncurrent asset associated with a defined benefit pension plan or other postretirement defined benefit plan.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The funded status is measured as the difference between the fair value of plan assets and the benefit obligation. Will normally be the same as the net Defined Benefit Plan, Amounts Recognized in Balance Sheet, Total.

+ References

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- Details

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