Retirement and Deferred Compensation Plans - Additional Information (Details) $ in Millions	1 Months Ended		12 Months Ended
	Feb. 29, 2020 USD ($)	Jan. 31, 2020 USD ($)	Dec. 31, 2020 USD ($) Insurance_contract	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Settlement of lump sum payments	$ 3.2
Pension liability			$ 6.6
Remaining plan assets in excess of pension liability			16.6
Pension liability			9.3
Deferred compensation plans, asset and liability			118.4	$ 106.2
Company Sponsored Plans
Defined Benefit Plan Disclosure [Line Items]
Total expense			16.6	16.9	$ 17.7
Statutory Plans
Defined Benefit Plan Disclosure [Line Items]
Total expense			27.5	32.1	$ 37.4
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Remaining plan assets in excess of pension liability			368.8	80.4
Accumulated benefit obligation for plan			841.6	717.2
Accumulated benefit obligation for plans that do not have plan assets			115.4	100.4
Estimated employer contribution to pension plans during next fiscal year			16.0
Pension Plan | Qualified Plan
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation for plan			957.0	817.6
Projected benefit obligation for plans			994.1	847.6
Retiree health care plan
Defined Benefit Plan Disclosure [Line Items]
Net loss recognized in accumulated other comprehensive loss			2.3	1.5
Prior service cost (credit) recognized in accumulated other comprehensive loss			$ (2.9)	$ (3.5)
Discount rate used in measurement of benefit obligation (as a percent)			2.20%	3.00%
Discount rate used in measurement of net periodic benefit cost (as a percent)			3.00%	4.20%	3.20%
Health care cost trend rate assumed for next fiscal year (as a percent)			6.50%
Ultimate health care cost trend rate (as a percent)			4.50%
Non-United States Plans
Defined Benefit Plan Disclosure [Line Items]
Pension liability			$ 2.7
Non-United States Plans | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Settlement of lump sum payments			$ 42.2	$ 40.9
Expected long-term return on plan assets			2.20%	2.70%	2.70%
Number of foreign plans using guaranteed insurance contracts | Insurance_contract			4
Net loss recognized in accumulated other comprehensive loss			$ 95.2	$ 50.5
Prior service cost (credit) recognized in accumulated other comprehensive loss			$ 7.6	$ 7.8
Discount rate used in measurement of benefit obligation (as a percent)			0.60%	1.10%
Non-United States Plans | Pension Plan | Minimum
Defined Benefit Plan Disclosure [Line Items]
Expected long-term return on plan assets			0.60%
Non-United States Plans | Pension Plan | Maximum
Defined Benefit Plan Disclosure [Line Items]
Expected long-term return on plan assets			3.00%
United States Plans
Defined Benefit Plan Disclosure [Line Items]
Contributions to pension plans		$ 19.2
United States Plans | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Settlement of lump sum payments			$ 22.3
Expected long-term return on plan assets			0.00%	4.30%	4.50%
Net loss recognized in accumulated other comprehensive loss			$ 8.6	$ 15.8
Discount rate used in measurement of benefit obligation (as a percent)			2.10%	2.50%