Income Taxes (Tables)

12 Months Ended

Mar. 31, 2017

A reconciliation of income tax (benefit) expense to the federal statutory rate follows (in thousands):


	Year Ended March 31,
	2017		2016
Federal income tax at the statutory rate	$	(8,127)	$	(8,558)
State taxes, net of federal effect		(225)		(250)
Foreign taxes		31		109
R&D tax credit		(298)		(451)
Impact of state rate change		(270)		478
Warrant liability		(474)		—
Valuation allowance		5,918		5,596
Shortfall in tax benefit—stock compensation		3,352		3,058
Other		112		38
Income tax expense (benefit)	$	19	$	20

The Company’s deferred tax assets and liabilities consisted of the following at March 31, 2017 and 2016 (in thousands):


	2017		2016
Deferred tax assets:
Inventories	$	2,921	$	2,903
Warranty reserve		1,383		616
Bad debt reserve		2,514		3,350
Deferred revenue		1,254		1,101
Net operating loss (“NOL”) carryforwards		244,874		226,007
Tax credit carryforwards		19,784		19,411
Depreciation, amortization and impairment loss		2,505		3,045
Other		2,517		4,212
Deferred tax assets		277,752		260,645
Valuation allowance for deferred tax assets		(269,299)		(252,349)
Deferred tax assets, net of valuation allowance		8,453		8,296
Deferred tax liabilities:
Federal benefit of state taxes		(8,453)		(8,296)
Net deferred tax assets	$	—	$	—

The Company’s NOL and tax credit carryforwards for federal and state income tax purposes at March 31, 2017 were as follows (in thousands):


			Expiration
	Amount		Period
Federal NOL	$	677,995	2018 - 2035
State NOL	$	160,223	2017 - 2035
Federal tax credit carryforwards	$	10,093	2018 - 2035
State tax credit carryforwards	$	9,692	Indefinite

A reconciliation of the beginning and ending amount of total gross unrecognized tax benefits is as follows (in thousands):


Balance at March 31, 2015	$	2,564
Gross increase related to prior year tax positions		13
Gross increase related to current year tax positions		124
Lapse of statute of limitations		—
Balance at March 31, 2016	$	2,701
Gross increase related to prior year tax positions		—
Gross increase related to current year tax positions		124
Lapse of statute of limitations		—
Balance at March 31, 2017	$	2,825