Business Segments (Reconciliation Of Segment Results To Consolidated Income Before Income Taxes) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Segment Reporting [Abstract]
Income from construction operations	$ 68,753	$ 57,696	$ 118,457	$ 104,923
Other income (expense)	1,431	(797)	1,606	(316)
Interest expense	(17,938)	(16,464)	(35,748)	(32,900)
Income before income taxes	$ 52,246	$ 40,435	$ 84,315	$ 71,707