Property And Equipment (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Property And Equipment [Abstract]
Lease Obligation Period	5 years
Amortization of assets held under capital leases	$ 41.9	$ 37.6	$ 31.7