Loan Receivable and Allowance for Loan and Lease Losses Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Jun. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Mar. 31, 2016
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses	$ 5,183	$ 3,975	$ 4,428	$ 5,232	$ 4,428	$ 4,428
Charge-off	344		283	354	864	1,422
Recoveries	68		104	233	198	731
Provision for loan losses	(160)	643	643	(364)	677	1,495
Allowance for loan losses	4,747	4,439	3,975	4,747	4,439	5,232
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment	4,288	4,242		4,288	4,242	4,642
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	459	197		459	197	590
Loans Receivable Ending Balance	529,145	562,771		529,145	562,771	589,019
Financing Receivable, Collectively Evaluated for Impairment	513,015	547,072		513,015	547,072	569,454
Financing Receivable, Individually Evaluated for Impairment	16,130	15,699		16,130	15,699	19,565
Residential Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses	1,875	1,640	1,970	1,697	1,970	1,970
Charge-off	59		13	62	243	389
Recoveries	0		1	0	1	113
Provision for loan losses	(162)		(52)	19	(152)	3
Allowance for loan losses	1,654	1,576	1,640	1,654	1,576	1,697
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment	1,423	1,479		1,423	1,479	1,602
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	231	97		231	97	95
Loans Receivable Ending Balance	130,687	128,855		130,687	128,855	143,667
Financing Receivable, Collectively Evaluated for Impairment	125,366	121,925		125,366	121,925	139,031
Financing Receivable, Individually Evaluated for Impairment	5,321	6,930		5,321	6,930	4,636
Multifamily [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses	530	410	502	622	502	502
Charge-off	244		3	251	241	340
Recoveries	0		0	0	0	0
Provision for loan losses	386		50	301	196	460
Allowance for loan losses	672	457	410	672	457	622
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment	672	457		672	457	622
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	0	0		0	0	0
Loans Receivable Ending Balance	74,818	109,287		74,818	109,287	95,648
Financing Receivable, Collectively Evaluated for Impairment	73,208	108,046		73,208	108,046	93,879
Financing Receivable, Individually Evaluated for Impairment	1,610	1,241		1,610	1,241	1,769
Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses	1,858	1,032	1,029	1,808	1,029	1,029
Charge-off	0		0	0	0	0
Recoveries	5		3	10	3	9
Provision for loan losses	(120)		401	(75)	404	770
Allowance for loan losses	1,743	1,436	1,032	1,743	1,436	1,808
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment	1,722	1,436		1,722	1,436	1,787
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	20	0		20	0	21
Loans Receivable Ending Balance	252,058	242,707		252,058	242,707	273,470
Financing Receivable, Collectively Evaluated for Impairment	249,215	240,845		249,215	240,845	267,176
Financing Receivable, Individually Evaluated for Impairment	2,843	1,862		2,843	1,862	6,294
Construction Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses	62	99	99	62	99	99
Charge-off	0		0	0	0	0
Recoveries	0		0	0	0	0
Provision for loan losses	(12)		0	(12)	0	(37)
Allowance for loan losses	50	99	99	50	99	62
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment	50	99		50	99	62
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	0	0		0	0	0
Loans Receivable Ending Balance	4,975	5,067		4,975	5,067	5,000
Financing Receivable, Collectively Evaluated for Impairment	4,975	5,067		4,975	5,067	5,000
Financing Receivable, Individually Evaluated for Impairment	0	0		0	0	0
Commercial Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses	856	791	813	1,022	813	813
Charge-off	0		8	0	120	176
Recoveries	63		95	219	188	578
Provision for loan losses	(342)		(35)	(664)	(38)	(193)
Allowance for loan losses	577	843	791	577	843	1,022
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment	370	743		370	743	548
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	208	100		208	100	474
Loans Receivable Ending Balance	66,357	76,766		66,357	76,766	71,192
Financing Receivable, Collectively Evaluated for Impairment	60,001	71,100		60,001	71,100	64,326
Financing Receivable, Individually Evaluated for Impairment	6,356	5,666		6,356	5,666	6,866
Consumer Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses	2	3	15	21	15	15
Charge-off	41		259	41	260	517
Recoveries	0		5	4	6	31
Provision for loan losses	41		279	18	267	492
Allowance for loan losses	2	28	$ 3	2	28	21
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment	2	28		2	28	21
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	0	0		0	0	0
Loans Receivable Ending Balance	250	89		250	89	42
Financing Receivable, Collectively Evaluated for Impairment	250	89		250	89	42
Financing Receivable, Individually Evaluated for Impairment	0	$ 0		0	$ 0	0
Unallocated Financing Receivables [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses				0
Charge-off				0
Recoveries				0
Provision for loan losses				49
Allowance for loan losses	49			49		$ 0
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment	49			49
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	0			0
Loans Receivable Ending Balance	0			0
Financing Receivable, Collectively Evaluated for Impairment	0			0
Financing Receivable, Individually Evaluated for Impairment	$ 0			$ 0

Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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

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The balance of financing receivables that were collectively evaluated for impairment.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 6
-Section L
-Subsection 1

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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Amount of expense related to estimated loss from loan and lease transactions.

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