Employee Benefit Plans - Activity of Plan Assets With Fair Value Measurement Using Significant Unobservable Inputs (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value of plan assets at the beginning of the year	$ 174.9	$ 183.4
Foreign currency impact	0.4	(1.5)
Fair value of plan assets at the end of the year	190.2	174.9
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	33.3
Fair value of plan assets at the end of the year	35.3	33.3
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	80.1
Actual return on plan assets	3.3	(0.5)
Purchase, sales and settlements. net	(0.9)	(2.0)
Fair value of plan assets at the end of the year	82.6	80.1
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	50.6
Fair value of plan assets at the end of the year	52.0	50.6
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
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	50.6	55.2
Foreign currency impact	(1.0)	(2.1)
Fair value of plan assets at the end of the year	$ 52.0	$ 50.6

Amount, measured using unobservable inputs, of increase (decrease) in plan assets of defined benefit plan from actual return (loss) on assets still held.

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Period Type:	duration

- Definition

Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(iv)(01)
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-Publisher FASB
-Name Accounting Standards Codification
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+ Details

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

+ Details

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- Definition

Amount, measured using unobservable input, of increase (decrease) in plan asset of defined benefit plan from purchase, sale and settlement of trade associated with underlying investment.

+ References

+ Details

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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.

+ Details

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- Details

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- Details

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