Long-Lived Assets (Details Textual) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Goodwill And Intangible Assets Disclosure [Abstract]
Total amortization expense	$ 4.6	$ 6.7	$ 13.4	$ 20.0
Estimated total amortization expense 2018	18.0		18.0
Estimated total amortization expense 2019	16.1		16.1
Estimated total amortization expense 2020	13.2		13.2
Estimated total amortization expense 2021	9.2		9.2
Estimated total amortization expense 2022	$ 6.8		$ 6.8