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.

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- Definition

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+ References

No definition available.

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- 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

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- Definition

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

+ References

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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

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Retirement and Other Postretirement Benefit Plans - Schedule of Pension Assets Measured at Fair Value (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Fair value measurements	$ 214.3	$ 184.3
Equity Funds
Defined Benefit Plan Disclosure [Line Items]
Fair value measurements	28.2	44.4
Diversified Growth Funds
Defined Benefit Plan Disclosure [Line Items]
Fair value measurements	55.6	44.5
Fixed Income Gilts
Defined Benefit Plan Disclosure [Line Items]
Fair value measurements	19.9
Insurance contracts
Defined Benefit Plan Disclosure [Line Items]
Fair value measurements	4.4	4.2
Liability Driven Investments
Defined Benefit Plan Disclosure [Line Items]
Fair value measurements	29.7	31.7
Index Linked Gilts
Defined Benefit Plan Disclosure [Line Items]
Fair value measurements	73.5	57.0
Diversified Investment, Funds
Defined Benefit Plan Disclosure [Line Items]
Fair value measurements	2.4	2.0
Cash and Cash Equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value measurements	0.6	0.5
Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value measurements	0.6	0.5
Level 1 \| Cash and Cash Equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value measurements	0.6	0.5
Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value measurements	206.9	177.6
Level 2 \| Equity Funds
Defined Benefit Plan Disclosure [Line Items]
Fair value measurements	28.2	44.4
Level 2 \| Diversified Growth Funds
Defined Benefit Plan Disclosure [Line Items]
Fair value measurements	55.6	44.5
Level 2 \| Fixed Income Gilts
Defined Benefit Plan Disclosure [Line Items]
Fair value measurements	19.9
Level 2 \| Liability Driven Investments
Defined Benefit Plan Disclosure [Line Items]
Fair value measurements	29.7	31.7
Level 2 \| Index Linked Gilts
Defined Benefit Plan Disclosure [Line Items]
Fair value measurements	73.5	57.0
Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value measurements	6.8	6.2	$ 6.5
Actual return on plan assets	0.4	0.2
Purchases, sales and settlements	0.3	(0.2)
Currency translation adjustments	(0.1)	(0.3)
Level 3 \| Insurance contracts
Defined Benefit Plan Disclosure [Line Items]
Fair value measurements	4.4	4.2	4.2
Actual return on plan assets	0.1	0.2
Purchases, sales and settlements	0.2
Currency translation adjustments	(0.1)	(0.2)
Level 3 \| Diversified Investment, Funds
Defined Benefit Plan Disclosure [Line Items]
Fair value measurements	2.4	2.0	$ 2.3
Actual return on plan assets	0.3
Purchases, sales and settlements	$ 0.1	(0.2)
Currency translation adjustments		$ (0.1)