Note 2 - Revenue Recognition (Tables)

6 Months Ended

Sep. 30, 2020

Notes Tables

Disaggregation of Revenue [Table Text Block]

	Three Months Ended September 30, 2020				Six Months Ended September 30, 2020
Product Line:	Grid		Wind		Grid		Wind
Equipment and systems	$	15,261	$	4,059	$	31,798	$	6,676
Services and technology development		1,086		711		2,264		1,591
Total	$	16,347	$	4,770	$	34,062	$	8,267
Region:
Americas	$	15,677	$	30	$	26,231	$	42
Asia Pacific		370		4,734		6,385		8,002
EMEA		300		6		1,446		223
Total	$	16,347	$	4,770	$	34,062	$	8,267

	Three Months Ended September 30, 2019				Six Months Ended September 30, 2019
Product Line:	Grid		Wind		Grid		Wind
Equipment and systems	$	10,044	$	2,077	$	18,399	$	5,581
Services and technology development		1,445		446		2,946		856
Total	$	11,489	$	2,523	$	21,345	$	6,437
Region:
Americas	$	10,698	$	1	$	18,499	$	47
Asia Pacific		393		2,464		2,220		6,320
EMEA		398		58		626		70
Total	$	11,489	$	2,523	$	21,345	$	6,437

Contract with Customer, Contract Asset, Contract Liability, and Receivable [Table Text Block]

	Unbilled Accounts Receivable			Deferred Program Costs			Contract Liabilities
Beginning balance as of March 31, 2020	$	5,711		$	1,631		$	26,142
Increases for costs incurred to fulfill performance obligations		—			3,279			—
Increase (decrease) due to customer billings		(5,929	)		—			23,931
Decrease due to cost recognition on completed performance obligations		—			(3,314	)		—
Increase (decrease) due to recognition of revenue based on transfer of control of performance obligations		6,186			—			(28,678	)
Other changes and FX impact		0			18			561
Ending balance as of September 30, 2020	$	5,968		$	1,614		$	21,956

	Unbilled Accounts Receivable			Deferred Program Costs			Contract Liabilities
Beginning balance as of March 31, 2019	$	2,213		$	318		$	15,519
Increases for costs incurred to fulfill performance obligations		—			2,153			—
Increase (decrease) due to customer billings		(2,926	)		—			19,340
Decrease due to cost recognition on completed performance obligations		—			(310	)		—
Increase (decrease) due to recognition of revenue based on transfer of control of performance obligations		4,711			—			(18,534	)
Other changes and FX impact		(4	)		(9	)		(313	)
Ending balance as of September 30, 2019	$	3,994		$	2,152		$	16,012

Schedule of Revenue by Major Customers by Reporting Segments [Table Text Block]

		Three Months Ended						Six Months Ended
	Reportable	September 30,						September 30,
	Segment	2020			2019			2020			2019
EPC Services	Grid		12	%		0	%		18	%		0	%
Hoffman Construction	Grid		<10%			25	%		<10%			12	%
Inox Wind Limited	Wind		<10%			<10%			<10%			17	%
M.J. Electric, LLC	Grid		<10%			25	%		<10%			13	%
Micron Technology	Grid		<10%			<10%			<10%			14	%
Reed & Reed Inc.	Grid		25	%		0	%		12	%		0	%
Siemens Gamesa Renewable Energy Pty. Ltd.	Grid		<10%			0	%		13	%		0	%