Employee Benefits - Cash Flows Narrative (Details) $ in Millions	Dec. 31, 2020 USD ($)
Other Post-Retirement Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Expected amortization of prior service credit, next fiscal year	$ 0.4
Expected amortization of net gain, next fiscal year	0.2
Expected employer contributions during next fiscal year	5.0
U.S. \| Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Expected employer contributions during next fiscal year	95.0
U.K. \| Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Expected employer contributions during next fiscal year	8.0
Other \| Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Expected employer contributions during next fiscal year	$ 19.0

Amount included in accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan expected to be recognized in net periodic benefit (cost) credit for fiscal year following most recent annual statement of financial position.

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Amount of contribution expected to be received by defined benefit plan from employer in next fiscal year following current fiscal year.

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