Financial Assets Measured at Fair Value on Recurring Basis (Detail) (Fair Value, Measurements, Recurring [Member], USD $) In Thousands, unless otherwise specified	Sep. 30, 2014		Sep. 30, 2013
Assets:
Total	$ 19,077		$ 7,792
Cash
Assets:
Cash equivalents	10,326	[1]	685	[1]
Marketable securities
Assets:
Marketable securities available-for-sale	8,751	[2]	7,107	[2]
Active Markets for Identical Instruments (Level 1)
Assets:
Total	19,077		7,792
Active Markets for Identical Instruments (Level 1) | Cash
Assets:
Cash equivalents	10,326	[1]	685	[1]
Active Markets for Identical Instruments (Level 1) | Marketable securities
Assets:
Marketable securities available-for-sale	$ 8,751	[2]	$ 7,107	[2]

[1] Included in cash and cash equivalents on our balance sheet at September 30, 2014 and 2013. Not included in this table are cash deposits of $94.7 million and $82.5 million at September 30, 2014 and 2013, respectively.

[2] Represents securities held under a supplemental retirement and savings plan for certain officers and senior management employees, which are distributed upon termination or retirement of the employees. Included in long-term marketable securities on our balance sheet at September 30, 2014 and 2013.