Income Taxes - Additional Information (Details) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2018 USD ($) Transition	Sep. 30, 2017	Sep. 30, 2018 USD ($) Transition	Sep. 30, 2017	Dec. 31, 2017 USD ($)
Income Taxes [Line Items]
Corporate income tax rate			21.00%		35.00%
Number of foreign subsidiaries | Transition	1		1
Tax cuts and jobs act of 2017 net benefit to income tax expense					$ 1.2
Tax cuts and jobs act of 2017 due to change in tax rate deferred tax benefit					3.0
Tax cuts and jobs act of 2017 provisional income tax expense benefit					1.8
Tax cuts and jobs act of 2017 foreign earnings and profits tax rate liquid assets			15.50%
Tax cuts and jobs act of 2017 foreign earnings and profits tax rate liquid assets, unremitted foreign E&P			8.00%
Income tax expense reduction due to tax impact	$ 0.3		$ 0.3
Effective tax rate for the year	20.90%	37.90%	(5.10%)	40.10%
Unrecognized tax benefits that would impact effective tax rate	$ 0.4		$ 0.4		$ 0.4
Earliest Tax Year [Member] | State and Local [Member]
Income Taxes [Line Items]
Income tax examination for tax years			2013
Earliest Tax Year [Member] | Non-U.S [Member]
Income Taxes [Line Items]
Income tax examination for tax years			2014
Latest Tax Year [Member] | State and Local [Member]
Income Taxes [Line Items]
Income tax examination for tax years			2017
Latest Tax Year [Member] | Non-U.S [Member]
Income Taxes [Line Items]
Income tax examination for tax years			2017