Contract Assets and Liabilities (Schedule Of Contract Assets) (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Contract with Customer, Contract Asset, Contract Liability, and Receivable [Abstract]
Retention receivable	$ 563,967	$ 585,556
Costs and estimated earnings in excess of billings:
Claims	599,460	677,367
Unapproved change orders	619,888	601,681
Other unbilled costs and profits	80,438	98,480
Total costs and estimated earnings in excess of billings	1,299,786	1,377,528
Capitalized contract costs	42,606	49,441
Total contract assets	$ 1,906,359	$ 2,012,525