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Pension and Savings Plans (Details 4) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	$ 295.1	$ 281.2
Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of period	162.8	152.1
Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of period	301.0	301.0
Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of period	14.1	23.0
Equity Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of period	119.9	107.1
Equity Funds [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of period	119.9	107.1
Equity Funds [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of period	0.0	0.0
Equity Funds [Member] | Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of period	0.0	0.0
International equity securities | Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of period		0.0
U.S. debt securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of period	47.8	53.4
U.S. debt securities | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of period	25.1	26.8
U.S. debt securities | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of period	22.7	26.6
U.S. debt securities | Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of period	0.0
International debt securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of period	12.6	15.0
International debt securities | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of period	0.0	0.0
International debt securities | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of period	12.6	15.0
International debt securities | Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of period	0.0	0.0
Banks, Trust and Insurance, Equities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of period	109.0	97.3
Corporate Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of period	265.7	259.4
Corporate Debt Securities [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of period	0.0	0.0
Corporate Debt Securities [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of period	265.7	259.4
Corporate Debt Securities [Member] | Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of period	0.0	0.0
Short-term investments
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of period	17.8	18.2
Short-term investments | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of period	17.8	18.2
Short-term investments | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of period	0.0	0.0
Short-term investments | Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of period	0.0	0.0
Interests in real estate
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of period	14.1	23.0
Interests in real estate | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of period	0.0	0.0
Interests in real estate | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of period	0.0	0.0
Interests in real estate | Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of period	14.1	23.0	$ 30.2
Private Equity Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of period	186.1	183.9
Pension Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of period	773.0	757.3	$ 839.8
Fair Value Pension Plan Assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of period	$ 477.9	$ 476.1

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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 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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