Loan Receivable and Allowance for Loan and Lease Losses Allowance for Loan Losses (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Mar. 31, 2014
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses	$ 6,597	$ 9,399	$ 7,233	$ 10,989	$ 10,989
Charge-off	112	335	195	2,874	4,540
Recoveries	546	403	1,487	1,026	1,210
Provision for loan losses	(1,151)us-gaap_ProvisionForLoanAndLeaseLosses	(1,052)us-gaap_ProvisionForLoanAndLeaseLosses	(2,645)us-gaap_ProvisionForLoanAndLeaseLosses	(726)us-gaap_ProvisionForLoanAndLeaseLosses	(426)us-gaap_ProvisionForLoanAndLeaseLosses
Allowance for loan losses	5,880	8,415	5,880	8,415	7,233
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment	4,523	7,164	4,523	7,164	5,602
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	1,357	1,251	1,357	1,251	1,631
Loans Receivable Ending Balance	435,534	393,163	435,534	393,163	389,956
Financing Receivable, Collectively Evaluated for Impairment	418,276	366,235	418,276	366,235	367,454
Financing Receivable, Individually Evaluated for Impairment	17,258	26,928	17,258	26,928	22,502
One- to four family loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses	3,301	4,223	3,377	3,496	3,496
Charge-off	(112)	0	(195)	(1,619)	(2,887)
Recoveries	0	13	379	515	534
Provision for loan losses	225	(169)	(147)	1,675	2,234
Allowance for loan losses	3,414	4,067	3,414	4,067	3,377
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment	2,515	3,636	2,515	3,636	2,857
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	899	431	899	431	520
Loans Receivable Ending Balance	127,417	118,187	127,417	118,187	112,191
Financing Receivable, Collectively Evaluated for Impairment	120,367	110,268	120,367	110,268	105,719
Financing Receivable, Individually Evaluated for Impairment	7,050	7,919	7,050	7,919	6,472
Multifamily Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses	372	394	308	408	408
Charge-off	0	(98)	0	(98)	(98)
Recoveries	0	7	82	23	31
Provision for loan losses	(19)	78	(37)	48	(33)
Allowance for loan losses	353	381	353	381	308
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment	172	329	172	329	216
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	181	52	181	52	92
Loans Receivable Ending Balance	64,138	47,544	64,138	47,544	47,525
Financing Receivable, Collectively Evaluated for Impairment	62,648	46,181	62,648	46,181	45,285
Financing Receivable, Individually Evaluated for Impairment	1,490	1,363	1,490	1,363	2,240
Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses	1,154	2,888	1,835	3,298	3,298
Charge-off	0	(58)	0	(570)	(574)
Recoveries	2	0	256	0	0
Provision for loan losses	(291)	(610)	(1,226)	(508)	(889)
Allowance for loan losses	865	2,220	865	2,220	1,835
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment	832	1,971	832	1,971	1,580
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	32	249	32	249	255
Loans Receivable Ending Balance	200,334	194,019	200,334	194,019	198,101
Financing Receivable, Collectively Evaluated for Impairment	196,229	181,435	196,229	181,435	189,317
Financing Receivable, Individually Evaluated for Impairment	4,105	12,584	4,105	12,584	8,784
Construction Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses	214	210	0	0	0
Charge-off	0	0	0	0	0
Recoveries	0	149	0	149	149
Provision for loan losses	(53)	(359)	161	(149)	(149)
Allowance for loan losses	161	0	161	0	0
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment	161	0	161	0	0
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	0	0	0	0	0
Loans Receivable Ending Balance	5,074	5,068	5,074	5,068	5,070
Financing Receivable, Collectively Evaluated for Impairment	5,074	5,068	5,074	5,068	5,070
Financing Receivable, Individually Evaluated for Impairment	0	0	0	0	0
Business [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses	1,535	1,602	1,705	3,759	3,759
Charge-off	0	(179)	0	(572)	(966)
Recoveries	540	230	763	326	486
Provision for loan losses	(1,004)	112	(1,397)	(1,748)	(1,574)
Allowance for loan losses	1,071	1,765	1,071	1,765	1,705
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment	828	1,212	828	1,212	941
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	244	519	244	519	764
Loans Receivable Ending Balance	38,244	28,083	38,244	28,083	26,931
Financing Receivable, Collectively Evaluated for Impairment	33,638	23,022	33,638	23,022	21,926
Financing Receivable, Individually Evaluated for Impairment	4,606	5,061	4,606	5,061	5,005
Consumer Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses	21	29	8	28	28
Charge-off	0	0	0	(15)	(15)
Recoveries	4	4	7	13	10
Provision for loan losses	(9)	(51)	1	(44)	(15)
Allowance for loan losses	16	(18)	16	(18)	8
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment	15	16	15	16	8
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	1	0	1	0	0
Loans Receivable Ending Balance	327	262	327	262	138
Financing Receivable, Collectively Evaluated for Impairment	320	261	320	261	137
Financing Receivable, Individually Evaluated for Impairment	7	1	7	1	1
Unallocated Financing Receivables [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses		53
Charge-off		0
Recoveries		0
Provision for loan losses		(53)
Allowance for loan losses		$ 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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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.

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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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