Accrual for Warranty Costs (Detail) (USD $)	3 Months Ended		9 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013	Mar. 31, 2012
Product Warranties Disclosures [Abstract]
Balances, beginning of period	$ 361,000	$ 695,000	$ 526,000	$ 688,000
Accruals during the period	107,000	69,000	261,000	340,000
Changes in estimates of prior period accruals	20,000	(43,000)	(9,000)	104,000
Warranty expenditures	(89,000)	(122,000)	(379,000)	(533,000)
Balances, end of period	$ 399,000	$ 599,000	$ 399,000	$ 599,000