Loans and Allowance for Loan Losses - Association's Loan Portfolio Aging Analysis (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Jun. 30, 2017	Mar. 31, 2017
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Past Due	$ 9,986	$ 1,893
Current	453,861	445,061
Total loans	463,847	446,954	$ 443,143
Total Loans 90 Days Past Due & Accruing	338	155
Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Past Due	509	88
Current	137,470	133,753
Total loans	137,979	133,841	121,227
Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Past Due	184
Current	65,819	62,392
Total loans	66,003	62,392	57,801
Total Loans 90 Days Past Due & Accruing	11
Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Past Due	74	65
Current	7,720	7,840
Total loans	7,794	7,905	8,010
One- to Four-Family [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Past Due	8,479	1,714
Current	127,409	138,933
Total loans	135,888	140,647	144,718
Total Loans 90 Days Past Due & Accruing	327	155
Multi-Family [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Past Due	5
Current	93,885	87,228
Total loans	93,890	87,228	78,288
Home Equity Lines of Credit [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Past Due	36	26
Current	7,327	7,494
Total loans	7,363	7,520	7,452
Construction [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Past Due	699
Current	14,231	7,421
Total loans	14,930	7,421	$ 25,647
Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Past Due	2,211	1,081
Financing Receivables, 30 to 59 Days Past Due [Member] | Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Past Due	372	4
Financing Receivables, 30 to 59 Days Past Due [Member] | Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Past Due	112
Financing Receivables, 30 to 59 Days Past Due [Member] | Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Past Due	30	59
Financing Receivables, 30 to 59 Days Past Due [Member] | One- to Four-Family [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Past Due	963	1,016
Financing Receivables, 30 to 59 Days Past Due [Member] | Home Equity Lines of Credit [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Past Due	35	2
Financing Receivables, 30 to 59 Days Past Due [Member] | Construction [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Past Due	699
Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Past Due	755	248
Financing Receivables, 60 to 89 Days Past Due [Member] | Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Past Due	85	84
Financing Receivables, 60 to 89 Days Past Due [Member] | Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Past Due	44	6
Financing Receivables, 60 to 89 Days Past Due [Member] | One- to Four-Family [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Past Due	625	158
Financing Receivables, 60 to 89 Days Past Due [Member] | Home Equity Lines of Credit [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Past Due	1
Financing Receivables, 90 Days or Greater [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Past Due	7,020	564
Financing Receivables, 90 Days or Greater [Member] | Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Past Due	52
Financing Receivables, 90 Days or Greater [Member] | Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Past Due	72
Financing Receivables, 90 Days or Greater [Member] | One- to Four-Family [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Past Due	6,891	540
Financing Receivables, 90 Days or Greater [Member] | Multi-Family [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Past Due	$ 5
Financing Receivables, 90 Days or Greater [Member] | Home Equity Lines of Credit [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Past Due		$ 24