Business Segments (Reconciliation Of Segment Results To Consolidated Income Before Income Taxes) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Segment Reporting [Abstract]
Income (loss) from construction operations	$ 83,021	$ 47,943	$ 187,944	$ (270,861)
Other income (expense)	(8,048)	1,674	(8,364)	2,996
Interest expense	(25,613)	(17,305)	(58,513)	(51,252)
INCOME (LOSS) BEFORE INCOME TAXES	$ 49,360	$ 32,312	$ 121,067	$ (319,117)