Note 8 - Receivables, Net (Tables)

3 Months Ended

Mar. 31, 2021

Notes Tables

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

(in thousands)		March 31, 2021		December 31, 2020		March 31, 2020
Contracts completed and in progress:
Billed	$	190,775	$	293,376	$	250,683
Unbilled		136,565		148,159		141,514
Total contracts completed and in progress		327,340		441,535		392,197
Material sales		38,407		49,991		34,268
Other		111,904		52,736		52,645
Total gross receivables		477,651		544,262		479,110
Less: allowance for credit losses		2,491		3,450		1,392
Total net receivables	$	475,160	$	540,812	$	477,718