Accounts receivable, net

12 Months Ended

Dec. 31, 2022

Accounts Receivable, after Allowance for Credit Loss [Abstract]

Accounts receivable, net

Note 5. Accounts receivable, net

Accounts receivable consisted of the following:

(in thousands)	December 31, 2022			December 31, 2021
Trade receivables	$	35,367		$	38,597
Revenue recognized in excess of billings		14,844			72,676
Other receivables		25			147
Total		50,236			111,420
Allowance for doubtful accounts		(1,184	)		(3,872	)
Accounts receivable, net	$	49,052		$	107,548

Included in total receivables above are amounts billed under retainage provisions totaling $3.7 million and $11.6 million as of December 31, 2022, and 2021, respectively, which are due within the upcoming year.

At December 31, 2022, three customers accounted for approximately 55%, 15%, and 12%, respectively, of our total accounts receivable. At December 31, 2021, four customers accounted for approximately 29%, 23%, 19% and 18%, respectively, of total accounts receivable.

Activity in the allowance for doubtful accounts for each period was as follows:

	Year ended December 31,
(in thousands)	2022			2021			2020
Balance at beginning of period	$	3,872		$	1,228		$	441
Additions charged to earnings		5,578			4,045			787
Write-offs of uncollectible accounts		(8,266	)		(1,401	)		—
Balance at end of period	$	1,184		$	3,872		$	1,228