Loans Receivable And Allowance For Loan Losses: Schedule of Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2017	Mar. 31, 2016
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	$ 9,843	$ 9,889	$ 9,826	$ 9,924
Provision for (Recapture of) Loan Losses	(250)	0	(250)	0
Charge- offs	(9)	(58)	(19)	(135)
Recoveries	6	212	33	254
Allowance for loan losses, Ending Allowance	9,590	10,043	9,590	10,043
Mortgage loans, one-to-four family
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	1,177	1,420	1,239	1,480
Provision for (Recapture of) Loan Losses	(51)	(147)	(134)	(184)
Charge- offs	0	(2)	0	(28)
Recoveries	0	52	21	55
Allowance for loan losses, Ending Allowance	1,126	1,323	1,126	1,323
Mortgage loans, multi-family
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	400	373	473	392
Provision for (Recapture of) Loan Losses	80	(58)	7	(77)
Charge- offs	0	0	0	0
Recoveries	0	0	0	0
Allowance for loan losses, Ending Allowance	480	315	480	315
Mortgage loans, commercial
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	4,523	3,898	4,384	4,065
Provision for (Recapture of) Loan Losses	(199)	239	(55)	99
Charge- offs	(8)	(54)	(13)	(81)
Recoveries	0	0	0	0
Allowance for loan losses, Ending Allowance	4,316	4,083	4,316	4,083
Mortgage loans, construction - custom and owner/builder
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	636	555	619	451
Provision for (Recapture of) Loan Losses	59	(13)	76	91
Charge- offs	0	0	0	0
Recoveries	0	0	0	0
Allowance for loan losses, Ending Allowance	695	542	695	542
Mortgage loans, construction - speculative one-to-four family
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	100	122	130	123
Provision for (Recapture of) Loan Losses	(15)	(28)	(45)	(29)
Charge- offs	0	0	0	0
Recoveries	0	2	0	2
Allowance for loan losses, Ending Allowance	85	96	85	96
Mortgage loans, construction – commercial
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	282	486	268	426
Provision for (Recapture of) Loan Losses	(14)	131	0	191
Charge- offs	0	0	0	0
Recoveries	0	0	0	0
Allowance for loan losses, Ending Allowance	268	617	268	617
Mortgage loans, construction - Multi-family
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	385	336	316	283
Provision for (Recapture of) Loan Losses	(289)	(77)	(220)	(55)
Charge- offs	0	0	0	0
Recoveries	0	150	0	181
Allowance for loan losses, Ending Allowance	96	409	96	409
Mortgage loans, land
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	836	923	820	1,021
Provision for (Recapture of) Loan Losses	106	24	119	(72)
Charge- offs	0	0	(2)	(8)
Recoveries	5	7	10	13
Allowance for loan losses, Ending Allowance	947	954	947	954
Consumer loans, home equity and second mortgage
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	859	1,102	939	1,073
Provision for (Recapture of) Loan Losses	98	(81)	18	(39)
Charge- offs	0	0	0	(13)
Recoveries	0	0	0	0
Allowance for loan losses, Ending Allowance	957	1,021	957	1,021
Consumer loans, other
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	156	161	156	187
Provision for (Recapture of) Loan Losses	(26)	3	(24)	(21)
Charge- offs	(1)	(2)	(4)	(5)
Recoveries	1	0	2	1
Allowance for loan losses, Ending Allowance	130	162	130	162
Commercial business loans
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	489	513	482	423
Provision for (Recapture of) Loan Losses	1	7	8	96
Charge- offs	0	0	0	0
Recoveries	0	1	0	2
Allowance for loan losses, Ending Allowance	$ 490	$ 521	$ 490	$ 521

A valuation allowance for financing receivables that are expected to be uncollectible.

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- Definition

Amount of recovery of financing receivables doubtful of collection that were previously charged off.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of direct write-downs of financing receivables charged against the allowance.

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- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

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