Fair Value Measurements - Foreclosed Assets Remeasured and Reported at Fair Value (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Sep. 30, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Foreclosed Assets Remeasured at Initial Recognition Carrying Value Of Foreclosed Assets Prior To Remeasurement	$ 425	$ 975
Foreclosed Assets Remeasured at Initial Recognition Charge-offs recognized in the allowance for loan losses	(3)	(149)
Fair Value of Foreclosed Assets Remeasured at Initial Recognition	422	826
Foreclosed Assets Remeasured Subsequent to initial Recognition Carrying value of foreclosed assets prior to remeasurement	492	205
Foreclosed Assets Remeasured Subsequent to Initial Recognition Write-downs included in other non-interest expense	(217)	(36)
Fair Value of Foreclosed Assets remeasured subsequent to initial recognition	$ 275	$ 169