Leases (Supplemental Cash Flow And Balance Sheet Information) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
Leases [Abstract]
Operating cash flows from operating leases	$ 25,840
Right-of-use assets obtained in exchange for new operating lease liabilities	30,410
Lease right-of-use-assets	382,050	$ 369,333	$ 0
Current lease liabilities	82,429	86,747	0
Noncurrent lease liabilities	337,648	$ 331,520	$ 0
Total lease liabilities	$ 420,077
Operating lease, weighted average remaining lease term	6 years 9 months 18 days
Operating lease, weighted average discount rate	3.90%