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Retirement and Deferred Compensation Plans - Additional Information (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2019 USD ($) Insurance_contract | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($)
Defined Benefit Plan Disclosure [Line Items] |  |  |
Deferred compensation plans, asset and liability | $ 106.2 | $ 88.5 |
Company Sponsored Plans |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total expense | 16.9 | 17.7 | $ 17.6
Statutory Plans |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total expense | 32.1 | 37.4 | $ 35.6
Pension plans |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Accumulated benefit obligation for plans that have plan assets | 717.2 | 390.4 |
Accumulated benefit obligation for plans that do not have plan assets | 100.4 | $ 86.0 |
Estimated net loss that will be amortized from AOCI into net periodic benefit cost during next fiscal year | 3.1 |  |
Estimated prior service cost (credit) that will be amortized from AOCI into net periodic benefit cost during next fiscal year | 0.7 |  |
Estimated employer contribution to pension plans during next fiscal year | $ 16.0 |  |
Pension plans | Non-United States Plans |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Expected long-term return on plan assets | 2.70% | 2.70% | 2.80%
Number of foreign plans using guaranteed insurance contracts | Insurance_contract | 4 |  |
Net loss recognized in accumulated other comprehensive loss | $ 50.5 | $ 16.5 |
Prior service cost (credit) recognized in accumulated other comprehensive loss | $ 7.8 | $ 7.7 |
Discount rate used in measurement of benefit obligation (as a percent) | 1.10% | 2.40% |
Pension plans | Non-United States Plans | Minimum |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Expected long-term return on plan assets | 1.40% |  |
Pension plans | Non-United States Plans | Maximum |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Expected long-term return on plan assets | 3.50% |  |
Pension plans | United States Plans |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Expected long-term return on plan assets | 4.30% | 4.50% | 4.80%
Net loss recognized in accumulated other comprehensive loss | $ 15.8 | $ 13.7 |
Discount rate used in measurement of benefit obligation (as a percent) | 2.50% | 4.20% |
Retiree health care plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Estimated net loss that will be amortized from AOCI into net periodic benefit cost during next fiscal year | $ 0.1 |  |
Estimated prior service cost (credit) that will be amortized from AOCI into net periodic benefit cost during next fiscal year | 0.8 |  |
Net loss recognized in accumulated other comprehensive loss | 1.5 | $ 0.9 |
Prior service cost (credit) recognized in accumulated other comprehensive loss | $ (3.5) | $ (4.1) |
Discount rate used in measurement of benefit obligation (as a percent) | 3.00% | 4.20% |
Discount rate used in measurement of net periodic benefit cost (as a percent) | 4.20% | 3.20% | 4.00%
Health care cost trend rate assumed for next fiscal year (as a percent) | 6.80% |  |
Ultimate health care cost trend rate (as a percent) | 4.50% |  |

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