Long-Lived Assets (Details Textual) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Goodwill And Intangible Assets Disclosure [Abstract]
Total amortization expense	$ 4.0	$ 6.9
Estimated total amortization expense 2018	14.2
Estimated total amortization expense 2019	14.8
Estimated total amortization expense 2020	12.1
Estimated total amortization expense 2021	8.1
Estimated total amortization expense 2022	$ 6.4