401(k) Plan (Narrative) (Detail) (Napco and Subsidiaries 401 (k) Plan [Member], USD $)	3 Months Ended		6 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013	Dec. 31, 2012
Napco and Subsidiaries 401 (k) Plan [Member]
Schedule of Deferred Compensation Plans [Line Items]
Deferred compensation plan expense	$ 25,000	$ 23,000	$ 51,000	$ 44,000