Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2013
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 11,947	$ 12,031	$ 15,167
Other comprehensive (loss) income, net of tax:
Unrealized holding (losses) gains on available-for-sale securities arising during the period	(1,208)	1,559	235
Reclassification adjustment for realized gains included in net income	(315)	(89)	(217)
Other comprehensive (loss) income	(1,523)	1,470	18
Comprehensive income	$ 10,424	$ 13,501	$ 15,185