Contingent Liabilities - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Jul. 25, 2012	Aug. 10, 2011
Contingencies And Commitments [Line Items]
Cost of annuitization of benefits			$ 579
Cost of obtaining the letter of credit		9	1
Letters of Credit Outstanding, Amount		908
Collateral deposit for letter of credit	$ 908