Note 8 - Receivables, Net (Tables)

6 Months Ended

Jun. 30, 2021

Notes Tables

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

(in thousands)		June 30, 2021		December 31, 2020		June 30, 2020
Contracts completed and in progress:
Billed	$	259,319	$	293,376	$	311,550
Unbilled		217,025		148,159		163,815
Total contracts completed and in progress		476,344		441,535		475,365
Material sales		66,929		49,991		58,514
Other		105,930		52,736		65,462
Total gross receivables		649,203		544,262		599,341
Less: allowance for credit losses		2,263		3,450		2,419
Total net receivables	$	646,940	$	540,812	$	596,922