Fair Value Measurements and Fair Value of Financial Instruments, Assets Measured on Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Jun. 30, 2019
Assets [Abstract]
Securities available-for-sale	$ 192,999	$ 122,728
Equity securities	265	253
Recurring [Member]
Assets [Abstract]
Securities available-for-sale	192,999	122,728
Equity securities	265	253
Total securities measured at fair value	193,264	122,981
Recurring [Member] \| U.S. Government Sponsored Enterprises [Member]
Assets [Abstract]
Securities available-for-sale	4,530	5,553
Recurring [Member] \| State and Political Subdivisions [Member]
Assets [Abstract]
Securities available-for-sale	148,332	96,570
Recurring [Member] \| Mortgage-backed Securities-Residential [Member]
Assets [Abstract]
Securities available-for-sale	10,316	2,645
Recurring [Member] \| Mortgage-backed Securities-Multi-family [Member]
Assets [Abstract]
Securities available-for-sale	25,282	16,410
Recurring [Member] \| Corporate Debt Securities [Member]
Assets [Abstract]
Securities available-for-sale	4,539	1,550
Recurring [Member] \| Level 1 [Member]
Assets [Abstract]
Securities available-for-sale	4,539	1,550
Equity securities	265	253
Total securities measured at fair value	4,804	1,803
Recurring [Member] \| Level 1 [Member] \| U.S. Government Sponsored Enterprises [Member]
Assets [Abstract]
Securities available-for-sale	0	0
Recurring [Member] \| Level 1 [Member] \| State and Political Subdivisions [Member]
Assets [Abstract]
Securities available-for-sale	0	0
Recurring [Member] \| Level 1 [Member] \| Mortgage-backed Securities-Residential [Member]
Assets [Abstract]
Securities available-for-sale	0	0
Recurring [Member] \| Level 1 [Member] \| Mortgage-backed Securities-Multi-family [Member]
Assets [Abstract]
Securities available-for-sale	0	0
Recurring [Member] \| Level 1 [Member] \| Corporate Debt Securities [Member]
Assets [Abstract]
Securities available-for-sale	4,539	1,550
Recurring [Member] \| Level 2 [Member]
Assets [Abstract]
Securities available-for-sale	188,460	121,178
Equity securities	0	0
Total securities measured at fair value	188,460	121,178
Recurring [Member] \| Level 2 [Member] \| U.S. Government Sponsored Enterprises [Member]
Assets [Abstract]
Securities available-for-sale	4,530	5,553
Recurring [Member] \| Level 2 [Member] \| State and Political Subdivisions [Member]
Assets [Abstract]
Securities available-for-sale	148,332	96,570
Recurring [Member] \| Level 2 [Member] \| Mortgage-backed Securities-Residential [Member]
Assets [Abstract]
Securities available-for-sale	10,316	2,645
Recurring [Member] \| Level 2 [Member] \| Mortgage-backed Securities-Multi-family [Member]
Assets [Abstract]
Securities available-for-sale	25,282	16,410
Recurring [Member] \| Level 2 [Member] \| Corporate Debt Securities [Member]
Assets [Abstract]
Securities available-for-sale	0	0
Recurring [Member] \| Level 3 [Member]
Assets [Abstract]
Securities available-for-sale	0	0
Equity securities	0	0
Total securities measured at fair value	0	0
Recurring [Member] \| Level 3 [Member] \| U.S. Government Sponsored Enterprises [Member]
Assets [Abstract]
Securities available-for-sale	0	0
Recurring [Member] \| Level 3 [Member] \| State and Political Subdivisions [Member]
Assets [Abstract]
Securities available-for-sale	0	0
Recurring [Member] \| Level 3 [Member] \| Mortgage-backed Securities-Residential [Member]
Assets [Abstract]
Securities available-for-sale	0	0
Recurring [Member] \| Level 3 [Member] \| Mortgage-backed Securities-Multi-family [Member]
Assets [Abstract]
Securities available-for-sale	0	0
Recurring [Member] \| Level 3 [Member] \| Corporate Debt Securities [Member]
Assets [Abstract]
Securities available-for-sale	$ 0	$ 0

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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118942338&loc=SL82898722-210454

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118954083&loc=d3e26610-111562

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563

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- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=99377092&loc=SL75136599-209740

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- Definition

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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