Income Taxes - Tax Credit Carryforward (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Tax Credit Carryforward [Line Items]
Tax Credit Carryforward, Deferred Tax Asset	$ 28.6	$ 28.3
Tax Credit Carryforward, Valuation Allowance	25.3	22.8
Unrecognized Tax Benefits	$ (3.1)	(3.9)
Tax Year 2017 [Member]
Tax Credit Carryforward [Line Items]
State net operating losses and credit expiration date	2018 - 2036
Tax Year 2018 [Member]
Tax Credit Carryforward [Line Items]
State net operating losses and credit expiration date	2019 - 2037
Foreign Tax Authority [Member]
Tax Credit Carryforward [Line Items]
Deferred Tax Assets, Operating Loss Carryforwards, Foreign	$ 21.2	21.9
Operating Loss Carryforwards, Valuation Allowance	$ 15.6	13.9
Foreign Tax Authority [Member] | Tax Year 2017 [Member]
Tax Credit Carryforward [Line Items]
Operating Loss Carryforwards, Expiration	2018 - Indefinite
Foreign Tax Authority [Member] | Tax Year 2018 [Member]
Tax Credit Carryforward [Line Items]
Operating Loss Carryforwards, Expiration	2019 - Indefinite
Foreign Tax Authority [Member] | Capital Loss Carryforward [Member]
Tax Credit Carryforward [Line Items]
Tax Credit Carryforward, Deferred Tax Asset	$ 6.4	6.5
Tax Credit Carryforward, Valuation Allowance	$ 6.4	6.5
Foreign Tax Authority [Member] | Capital Loss Carryforward [Member] | Tax Year 2017 [Member]
Tax Credit Carryforward [Line Items]
Tax Credit Carryforward, Expiration	2018 - Indefinite
Foreign Tax Authority [Member] | Capital Loss Carryforward [Member] | Tax Year 2018 [Member]
Tax Credit Carryforward [Line Items]
Tax Credit Carryforward, Expiration	2019 - Indefinite
State and Local Jurisdiction [Member]
Tax Credit Carryforward [Line Items]
Tax Credit Carryforward, Valuation Allowance	$ 3.3	2.4
Deferred Tax Assets, State Taxes	$ 4.1	$ 3.8