Retirement and Deferred Compensation Plans - Fair Value of Pension Plan Assets by Asset Category (Details) - Pension plans - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
United States Plans
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 36.1	$ 38.7	$ 37.3
United States Plans | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	6.3	12.3
United States Plans | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	29.8	26.4
United States Plans | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
United States Plans | United States companies
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	6.3	12.3
United States Plans | United States companies | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	6.3	12.3
United States Plans | United States companies | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
United States Plans | United States companies | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
United States Plans | International companies
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
United States Plans | International companies | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
United States Plans | International companies | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
United States Plans | International companies | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
United States Plans | Government bonds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	18.4	15.2
United States Plans | Government bonds | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
United States Plans | Government bonds | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	18.4	15.2
United States Plans | Government bonds | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
United States Plans | Corporate bonds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	6.3	11.0
United States Plans | Corporate bonds | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
United States Plans | Corporate bonds | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	6.3	11.0
United States Plans | Corporate bonds | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
United States Plans | Guaranteed insurance contracts
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
United States Plans | Guaranteed insurance contracts | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
United States Plans | Guaranteed insurance contracts | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
United States Plans | Guaranteed insurance contracts | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
United States Plans | Annuity contract
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
United States Plans | Annuity contract | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
United States Plans | Annuity contract | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
United States Plans | Annuity contract | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
United States Plans | Bank loans
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0
United States Plans | Bank loans | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0
United States Plans | Bank loans | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0
United States Plans | Bank loans | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0
United States Plans | Unitized funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		0.0
United States Plans | Unitized funds | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		0.0
United States Plans | Unitized funds | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		0.0
United States Plans | Unitized funds | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		0.0
United States Plans | Real estate funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
United States Plans | Real estate funds | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
United States Plans | Real estate funds | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
United States Plans | Real estate funds | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
United States Plans | Insurance contracts
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
United States Plans | Insurance contracts | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
United States Plans | Insurance contracts | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
United States Plans | Insurance contracts | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
United States Plans | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	5.1	0.2
United States Plans | Cash and cash equivalents | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
United States Plans | Cash and cash equivalents | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	5.1	0.2
United States Plans | Cash and cash equivalents | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Non-United States Plans
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	354.1	376.7	$ 324.5
Non-United States Plans | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	66.0	81.8
Non-United States Plans | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	134.2	186.1
Non-United States Plans | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	153.9	108.8
Non-United States Plans | United States companies
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	16.6	15.2
Non-United States Plans | United States companies | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	16.6	15.2
Non-United States Plans | United States companies | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Non-United States Plans | United States companies | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Non-United States Plans | International companies
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	13.9	35.7
Non-United States Plans | International companies | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	13.9	35.7
Non-United States Plans | International companies | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Non-United States Plans | International companies | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Non-United States Plans | Government bonds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	55.5	45.2
Non-United States Plans | Government bonds | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Non-United States Plans | Government bonds | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	55.5	45.2
Non-United States Plans | Government bonds | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Non-United States Plans | Corporate bonds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	43.9	59.8
Non-United States Plans | Corporate bonds | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Non-United States Plans | Corporate bonds | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	43.9	59.8
Non-United States Plans | Corporate bonds | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Non-United States Plans | Guaranteed insurance contracts
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	17.7	17.6
Non-United States Plans | Guaranteed insurance contracts | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Non-United States Plans | Guaranteed insurance contracts | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	17.7	17.6
Non-United States Plans | Guaranteed insurance contracts | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Non-United States Plans | Annuity contract
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	46.2	55.3
Non-United States Plans | Annuity contract | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Non-United States Plans | Annuity contract | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	55.3
Non-United States Plans | Annuity contract | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	46.2	0.0
Non-United States Plans | Bank loans
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	8.9
Non-United States Plans | Bank loans | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0
Non-United States Plans | Bank loans | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	8.9
Non-United States Plans | Bank loans | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0
Non-United States Plans | Unitized funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		25.8
Non-United States Plans | Unitized funds | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		25.8
Non-United States Plans | Unitized funds | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		0.0
Non-United States Plans | Unitized funds | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		$ 0.0
Non-United States Plans | Equity securities
Defined Benefit Plan Disclosure [Line Items]
Percentage of investment in plan assets		60.00%
Non-United States Plans | Fixed income securities
Defined Benefit Plan Disclosure [Line Items]
Percentage of investment in plan assets		30.00%
Non-United States Plans | Cash
Defined Benefit Plan Disclosure [Line Items]
Percentage of investment in plan assets		10.00%
Non-United States Plans | Real estate funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	8.2	$ 8.2
Non-United States Plans | Real estate funds | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Non-United States Plans | Real estate funds | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	8.2	8.2
Non-United States Plans | Real estate funds | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Non-United States Plans | Insurance contracts
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	107.7	108.8
Non-United States Plans | Insurance contracts | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Non-United States Plans | Insurance contracts | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Non-United States Plans | Insurance contracts | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	107.7	108.8
Non-United States Plans | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	35.5	5.1
Non-United States Plans | Cash and cash equivalents | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	35.5	5.1
Non-United States Plans | Cash and cash equivalents | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Non-United States Plans | Cash and cash equivalents | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 0.0	$ 0.0