Employee Benefit Plans (Activity of Plan Assets With Fair Value Measurement Using Significant Unobservable Inputs) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value of plan assets at the beginning of the year	$ 159.7	$ 147.2
Actual return on plan assets	10.0	4.4
Foreign currency impact	12.4	(2.2)
Fair value of plan assets at the end of the year	183.4	159.7
Corporate Bonds, Debentures
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value of plan assets at the beginning of the year	32.0
Fair value of plan assets at the end of the year	32.5	32.0
Investment and Insurance Contacts
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value of plan assets at the beginning of the year	69.6
Fair value of plan assets at the end of the year	82.4	69.6
Significant Unobservable Inputs (Level 3)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value of plan assets at the beginning of the year	47.2	47.6
Actual return on plan assets	1.5	3.3
Purchase, sales and settlements	(0.3)	(1.0)
Foreign currency impact	6.8	(2.7)
Fair value of plan assets at the end of the year	55.2	47.2
Significant Unobservable Inputs (Level 3) \| Corporate Bonds, Debentures
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value of plan assets at the beginning of the year	0.0	0.6
Actual return on plan assets	0.0	0.0
Purchase, sales and settlements	0.0	(0.6)
Foreign currency impact	0.0	0.0
Fair value of plan assets at the end of the year	0.0	0.0
Significant Unobservable Inputs (Level 3) \| Investment and Insurance Contacts
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value of plan assets at the beginning of the year	47.2	47.0
Actual return on plan assets	1.5	3.3
Purchase, sales and settlements	(0.3)	(0.4)
Foreign currency impact	6.8	(2.7)
Fair value of plan assets at the end of the year	$ 55.2	$ 47.2

Amount of increase (decrease) in plan assets of defined benefit plan from actual return (loss) determined by change in fair value of plan assets adjusted for contributions, benefit payments, and other expenses.

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)(1)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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Period Type:	duration

- Definition

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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- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) plan assets of defined benefit plan.

+ 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)(2)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- Definition

Amount, measured using unobservable inputs, of increase (decrease) in plan assets of defined benefit plan from purchases, sales and settlements.

+ 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 (d)(5)(iv)(02)(B)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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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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