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Income Taxes (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Operating Loss Carryforwards [Line Items]
GILTI income tax expense (benefit)	$ 0.1
Provisional tax benefit from remeasurement of deferred tax liabilities		$ 16.2
Transition tax for foreign earnings		$ 3.9
Statutory tax rate, percentage	21.00%	35.00%	35.00%
Deferred tax assets, net of operating losses	$ 11.9
Deferred tax assets, net of operating losses	1.2
Undistributed earnings of foreign subsidiaries	30.0
Cash held in foreign operations	22.5
Unrecognized tax benefits that would affect the effective tax rate	$ 0.3	$ 3.5
Minimum
Operating Loss Carryforwards [Line Items]
Statute of limitations expiration period, in years	4 years
Maximum
Operating Loss Carryforwards [Line Items]
Statute of limitations expiration period, in years	10 years
RBI
Operating Loss Carryforwards [Line Items]
Unrecognized tax benefits that would affect the effective tax rate		$ 3.1
Federal
Operating Loss Carryforwards [Line Items]
Deferred tax assets, net of operating losses	$ 0.6
Deferred tax assets, net of operating losses	0.1
State
Operating Loss Carryforwards [Line Items]
Deferred tax assets, net of operating losses	9.6
Deferred tax assets, net of operating losses	0.6
Foreign Tax Authority
Operating Loss Carryforwards [Line Items]
Deferred tax assets, net of operating losses	1.7
Deferred tax assets, net of operating losses	$ 0.5

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