Commitments And Contingencies (Changes in Self-insurance Liability) (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Litigation of Recorded Insurance Receivable			$ 113,600
Adjustment to self insurance reserves	$ (55,200)	$ (29,600)	(55,200)	$ (62,200)	$ 69,300
Insurance Related Expenses [Roll Forward]
Balance, beginning of period			924,563	995,692
Reserves provided			40,784	16,085
Payments			(134,289)	(87,214)
Balance, end of period	$ 831,058	$ 924,563	$ 831,058	$ 924,563	$ 995,692