Note 9 - Warranty (Tables)

3 Months Ended

Jul. 31, 2013

Product Warranties Disclosures [Abstract]

Schedule of Product Warranty Liability [Table Text Block]

	Three Months Ended July 31,
	2013			2012
Warranty reserve balance at beginning of period	$	90		$	163
Expense accrued, including adjustments		25			9
Warranty costs incurred		(21	)		(24	)
Warranty reserve balance at end of period	$	94		$	148