Federal Income Taxes: Schedule of Effective Income Tax Rate Reconciliation (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2013
Income Tax Disclosure [Abstract]
Expected tax provision at statutory rate									$ 4,268	$ 2,941	$ 2,472
BOLI income									(184)	(180)	(196)
Change in estimated utilization of net capital loss carry-forward									0	0	281
Dividends on ESOP									(58)	(41)	(24)
Other - net									166	80	(19)
Provision for federal income taxes	$ 1,563	$ 776	$ 1,128	$ 676	$ 825	$ 685	$ 537	$ 802	$ 4,192	$ 2,800	$ 2,514