Loans and Allowance for Loan Losses - Summary of Impaired Loans (Detail) - USD ($) $ in Thousands	12 Months Ended
Jun. 30, 2016	Jun. 30, 2015
Financing Receivable, Impaired [Line Items]
Specific Allowance	$ 20	$ 91
Recorded Balance	4,261	4,907
Unpaid Principal Balance	4,261	4,907
Specific Allowance	20	91
Average Investment in Impaired Loans	4,385	5,026
Interest Income Recognized	100
Interest Income Recognized		94
Interest on Cash Basis	136	135
One- to Four-Family [Member]
Financing Receivable, Impaired [Line Items]
Recorded Balance, Loans without a specific allowance	2,291	2,801
Unpaid Principal Balance, Loans without a specific allowance	2,291	2,801
Specific Allowance, Loans without a specific allowance	0	0
Average Investment in Impaired Loans, Loans without a specific allowance	2,338	2,851
Interest Income Recognized, Loans without a specific allowance	32	18
Interest on Cash Basis, Loans without a specific allowance	42	31
Recorded Balance, Loans with a specific allowance	114	473
Unpaid Principal Balance, Loans with a specific allowance	114	473
Specific Allowance	6	57
Average Investment in Impaired Loans, Loans with a specific allowance	117	487
Interest Income Recognized, Loans with a specific allowance	1
Interest Income Recognized, Loans with a specific allowance		6
Interest on Cash Basis, Loans with a specific allowance	2	11
Recorded Balance	2,405	3,274
Unpaid Principal Balance	2,405	3,274
Specific Allowance	6	57
Average Investment in Impaired Loans	2,455	3,338
Interest Income Recognized	33
Interest Income Recognized		24
Interest on Cash Basis	44	42
Multi-Family [Member]
Financing Receivable, Impaired [Line Items]
Recorded Balance, Loans without a specific allowance	1,457	1,537
Unpaid Principal Balance, Loans without a specific allowance	1,457	1,537
Specific Allowance, Loans without a specific allowance	0	0
Average Investment in Impaired Loans, Loans without a specific allowance	1,497	1,573
Interest Income Recognized, Loans without a specific allowance	67	69
Interest on Cash Basis, Loans without a specific allowance	90	92
Recorded Balance	1,457	1,537
Unpaid Principal Balance	1,457	1,537
Average Investment in Impaired Loans	1,497	1,573
Interest Income Recognized	67
Interest Income Recognized		69
Interest on Cash Basis	90	92
Home Equity Lines of Credit [Member]
Financing Receivable, Impaired [Line Items]
Recorded Balance, Loans without a specific allowance	327	8
Unpaid Principal Balance, Loans without a specific allowance	327	8
Specific Allowance, Loans without a specific allowance	0	0
Average Investment in Impaired Loans, Loans without a specific allowance	346	9
Interest on Cash Basis, Loans without a specific allowance	2
Recorded Balance	327	8
Unpaid Principal Balance	327	8
Average Investment in Impaired Loans	346	9
Interest on Cash Basis	2
Construction [Member]
Financing Receivable, Impaired [Line Items]
Specific Allowance, Loans without a specific allowance	0	0
Commercial [Member]
Financing Receivable, Impaired [Line Items]
Recorded Balance, Loans without a specific allowance	28
Unpaid Principal Balance, Loans without a specific allowance	28
Specific Allowance, Loans without a specific allowance	0	0
Average Investment in Impaired Loans, Loans without a specific allowance	29
Recorded Balance, Loans with a specific allowance	35	46
Unpaid Principal Balance, Loans with a specific allowance	35	46
Specific Allowance	14	25
Average Investment in Impaired Loans, Loans with a specific allowance	40	50
Recorded Balance	63	46
Unpaid Principal Balance	63	46
Specific Allowance	14	25
Average Investment in Impaired Loans	69	50
Commercial [Member]
Financing Receivable, Impaired [Line Items]
Recorded Balance, Loans without a specific allowance	9	21
Unpaid Principal Balance, Loans without a specific allowance	9	21
Specific Allowance, Loans without a specific allowance	0	0
Average Investment in Impaired Loans, Loans without a specific allowance	15	25
Recorded Balance	9	21
Unpaid Principal Balance	9	21
Average Investment in Impaired Loans	15	25
Consumer [Member]
Financing Receivable, Impaired [Line Items]
Recorded Balance, Loans without a specific allowance		6
Unpaid Principal Balance, Loans without a specific allowance		6
Specific Allowance, Loans without a specific allowance	0	0
Average Investment in Impaired Loans, Loans without a specific allowance	3	9
Recorded Balance, Loans with a specific allowance		15
Unpaid Principal Balance, Loans with a specific allowance		15
Specific Allowance		9
Average Investment in Impaired Loans, Loans with a specific allowance		22
Interest Income Recognized, Loans with a specific allowance		1
Interest on Cash Basis, Loans with a specific allowance		1
Recorded Balance		21
Unpaid Principal Balance		21
Specific Allowance		9
Average Investment in Impaired Loans	$ 3	31
Interest Income Recognized		1
Interest on Cash Basis		$ 1

Impaired financing receivable interest income loss accrual method.

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
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Amount of allowance for credit losses related to recorded investment.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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