Revenues and expenses associated with the operations of AMPAC-ISP (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Assets Held For Sale [Line Items]
Revenues		$ 12,797
Operating income (loss) before tax	14	399
Income tax benefit (expenses)	5	283
Net income from discontinued operations	9	116
Adjustment to gain on sale of discontinued operations before tax	(7)
Income tax benefit (expenses)	(2)
Net gain on sale of discontinued operations	(5)
Income from discontinued operations, net of tax	$ 4	$ 116