Revenue Recognition (Contract with Customer, Asset and Liability) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2019
Revenue from Contract with Customer [Abstract]
Accounts receivable (including long-term, included in Other assets)	$ 1,018,105	$ 1,121,834
Contract assets, short-term (included in Other current assets)	9,131	7,283
Contract assets, long-term (included in Other assets)	8,136	9,964
Contract liabilities (Deferred revenue)	55,424	$ 63,921
Revenue recognized relating to the contract liability	$ 50,200