Note 8 - Receivables, Net (Tables)

9 Months Ended

Sep. 30, 2021

Notes Tables

Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block]

(in thousands)		September 30, 2021		December 31, 2020		September 30, 2020
Contracts completed and in progress:
Billed	$	278,313	$	293,376	$	355,293
Unbilled		217,534		148,159		167,311
Total contracts completed and in progress		495,847		441,535		522,604
Material sales		80,357		49,991		70,918
Other		110,302		52,736		71,691
Total gross receivables		686,506		544,262		665,213
Less: allowance for credit losses		1,684		3,450		3,265
Total net receivables	$	684,822	$	540,812	$	661,948