Supplemental Cash Flow Information (Schedule of Cash Flow, Supplemental Disclosures) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Supplemental Cash Flow Information [Abstract]
Interest (net of amounts capitalized)	$ 73,574	$ 92,926	$ 18,151
Income taxes	$ 40,139	$ 12,834	$ 0