Employee Stock Ownership Plan (Additional Information) (Detail) - USD ($)		9 Months Ended
	Oct. 06, 2008	Jun. 30, 2016	Jun. 30, 2017	Sep. 30, 2016
Total ESOP shares	203,363		161,987	172,870
Employee Stock Ownership Plan (ESOP), Weighted Average Purchase Price of Shares Purchased	$ 10.00
Employee Stock Ownership Plan (ESOP), Compensation Expense		$ 628,000