Revenue (Schedule Of Revenue By Contract Type) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Disaggregation of Revenue [Line Items]
Revenue	$ 3,880,227	$ 3,790,755	$ 4,641,830
Adverse Legal Ruling Pertaining To Mixed-Use Project In New York
Disaggregation of Revenue [Line Items]
Loss contingency	83,600
Fixed price
Disaggregation of Revenue [Line Items]
Revenue	2,728,175	2,466,326	3,140,148
Guaranteed maximum price
Disaggregation of Revenue [Line Items]
Revenue	530,137	612,924	905,704
Unit price
Disaggregation of Revenue [Line Items]
Revenue	327,077	359,900	363,786
Cost plus fee and other
Disaggregation of Revenue [Line Items]
Revenue	294,838	351,605	232,192
Civil
Disaggregation of Revenue [Line Items]
Revenue	1,883,865	1,734,882	2,095,760
Loss contingency	40,700
Civil | Fixed price
Disaggregation of Revenue [Line Items]
Revenue	1,618,081	1,441,547	1,815,079
Civil | Guaranteed maximum price
Disaggregation of Revenue [Line Items]
Revenue	(3,184)	1,142	2,854
Civil | Unit price
Disaggregation of Revenue [Line Items]
Revenue	235,085	274,293	268,377
Civil | Cost plus fee and other
Disaggregation of Revenue [Line Items]
Revenue	33,883	17,900	9,450
Building
Disaggregation of Revenue [Line Items]
Revenue	1,302,539	1,242,571	1,428,102
Building | Adverse Legal Ruling Pertaining To Mixed-Use Project In New York
Disaggregation of Revenue [Line Items]
Loss contingency	72,200
Building | Fixed price
Disaggregation of Revenue [Line Items]
Revenue	532,950	349,318	336,128
Building | Guaranteed maximum price
Disaggregation of Revenue [Line Items]
Revenue	532,538	595,907	888,345
Building | Unit price
Disaggregation of Revenue [Line Items]
Revenue	0	33	(1,373)
Building | Cost plus fee and other
Disaggregation of Revenue [Line Items]
Revenue	237,051	297,313	205,002
Specialty Contractors
Disaggregation of Revenue [Line Items]
Revenue	693,823	813,302	1,117,968
Specialty Contractors | Adverse Legal Ruling Pertaining To Mixed-Use Project In New York
Disaggregation of Revenue [Line Items]
Loss contingency	11,400
Specialty Contractors | Fixed price
Disaggregation of Revenue [Line Items]
Revenue	577,144	675,461	988,941
Specialty Contractors | Guaranteed maximum price
Disaggregation of Revenue [Line Items]
Revenue	783	15,875	14,505
Specialty Contractors | Unit price
Disaggregation of Revenue [Line Items]
Revenue	91,992	85,574	96,782
Specialty Contractors | Cost plus fee and other
Disaggregation of Revenue [Line Items]
Revenue	$ 23,904	$ 36,392	$ 17,740