Loans Receivable - Aging of Recorded Investment in Past Due Loans (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Jun. 30, 2019
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	$ 2,102	$ 2,869
Current	1,225,196	1,094,108
Total	1,227,298	1,096,977
30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	732	564
60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	226	333
90 Days or More Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	1,144	1,972
Residential [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	266,684	265,167
Commercial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	775,378	651,396
Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	24,929	13,231
Commercial Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	128,869	133,614
Home Equity Lines Of Credit [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	30,994	33,204
Consumer and Overdrafts [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	444	365
Originated [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	1,003	893
Current	1,141,129	994,277
Total	1,142,132	995,170
Originated [Member] | 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	385	344
Originated [Member] | 60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	12	150
Originated [Member] | 90 Days or More Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	606	399
Originated [Member] | Residential [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	634	86
Current	225,823	217,970
Total	226,457	218,056
Originated [Member] | Residential [Member] | 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	58
Originated [Member] | Residential [Member] | 90 Days or More Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	576	86
Originated [Member] | Commercial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	733,781	600,675
Total	733,781	600,675
Originated [Member] | Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	24,929	13,231
Total	24,929	13,231
Originated [Member] | Commercial Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	252	150
Current	128,431	133,286
Total	128,683	133,436
Originated [Member] | Commercial Loans [Member] | 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	252
Originated [Member] | Commercial Loans [Member] | 60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		150
Originated [Member] | Home Equity Lines Of Credit [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	117	656
Current	27,738	28,767
Total	27,855	29,423
Originated [Member] | Home Equity Lines Of Credit [Member] | 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	75	344
Originated [Member] | Home Equity Lines Of Credit [Member] | 60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	12
Originated [Member] | Home Equity Lines Of Credit [Member] | 90 Days or More Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	30	312
Originated [Member] | Consumer and Overdrafts [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		1
Current	427	348
Total	427	349
Originated [Member] | Consumer and Overdrafts [Member] | 90 Days or More Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		1
Acquired [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	1,099	1,976
Current	84,067	99,831
Total	85,166	101,807
Acquired [Member] | 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	347	220
Acquired [Member] | 60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	214	183
Acquired [Member] | 90 Days or More Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	538	1,573
Acquired [Member] | Residential [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	723	1,045
Current	39,504	46,066
Total	40,227	47,111
Acquired [Member] | Residential [Member] | 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	288	220
Acquired [Member] | Residential [Member] | 60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	214	116
Acquired [Member] | Residential [Member] | 90 Days or More Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	221	709
Acquired [Member] | Commercial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		568
Current	41,597	50,153
Total	41,597	50,721
Acquired [Member] | Commercial [Member] | 90 Days or More Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		568
Acquired [Member] | Commercial Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	186	178
Total	186	178
Acquired [Member] | Home Equity Lines Of Credit [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	376	363
Current	2,763	3,418
Total	3,139	3,781
Acquired [Member] | Home Equity Lines Of Credit [Member] | 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	59
Acquired [Member] | Home Equity Lines Of Credit [Member] | 60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		67
Acquired [Member] | Home Equity Lines Of Credit [Member] | 90 Days or More Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	317	296
Acquired [Member] | Consumer and Overdrafts [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	17	16
Total	$ 17	$ 16