Property and Equipment (Details Textual) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Property and Equipment (Textual) [Abstract]
Interest costs capitalized	$ 3.7	$ 1.1
Depreciation expense	103.5	98.9	$ 92.8
Assets under capital leases	17.1	17.1
Accumulated amortization related to capital leases	13.2	12.2
Depreciation expense related to capital leases	$ 1.0	$ 1.0	$ 1.0