Equity Investees (Schedule of Operations for Equity Investees) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
INCOME STATEMENT DATA:
Revenues	$ 790,612	$ 631,947
Operating income	49,381	51,671
Net income	(1,644)	(5,250)
Poseidon
INCOME STATEMENT DATA:
Revenues	40,895	31,189
Operating income	31,951	21,953
Net income	$ 28,676	$ 20,907