Revenue (Components of Contracts in Progress) (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Accounts Notes And Loans Receivable [Line Items]
Costs and earnings in excess of billings for contracts in progress	$ 45,743	$ 30,057
Costs and earnings in excess of billings for completed contracts	29,898	10,894
Total contract revenues in excess of billings	75,641	40,951
Current portion of contract revenues in excess of billings	74,535	39,844
Long-term contract revenues in excess of billings	1,106	1,107
Total billings in excess of contract revenues	(3,687)	(14,814)
Costs And Earnings In Excess Of Billings [Member]
Accounts Notes And Loans Receivable [Line Items]
Costs and earnings for contracts in progress	369,584	270,998
Amounts billed	(323,841)	(240,941)
Billings In Excess Of Costs And Earnings [Member]
Accounts Notes And Loans Receivable [Line Items]
Costs and earnings for contracts in progress	137,389	209,567
Amounts billed	$ (141,076)	$ (224,381)