Leases (Components Of Lease Expense) (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Lease Expense
Operating lease expense	[1]	$ 15,277	$ 12,728	$ 45,007	$ 35,181
Sublease income	[1]	(31)		(38)	(6)
Net lease expense	[1]	$ 15,246	$ 12,728	$ 44,969	$ 35,175

[1] Includes short-term leases and variable lease costs, which are immaterial. Included in both cost of services provided and goods sold and selling, general and administrative expenses.