Fair Value Measurements and Fair Value of Financial Instruments, Assets Measured on Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Jun. 30, 2018
Assets [Abstract]
Securities available-for-sale	$ 107,192	$ 120,806
Equity securities	215	217
Recurring [Member]
Assets [Abstract]
Securities available-for-sale	107,192	120,806
Equity securities	215	217
Total securities measured at fair value	107,407	121,023
Recurring [Member] \| U.S. Government Sponsored Enterprises [Member]
Assets [Abstract]
Securities available-for-sale	5,531	5,531
Recurring [Member] \| State and Political Subdivisions [Member]
Assets [Abstract]
Securities available-for-sale	80,438	92,255
Recurring [Member] \| Mortgage-backed Securities-Residential [Member]
Assets [Abstract]
Securities available-for-sale	2,859	3,247
Recurring [Member] \| Mortgage-backed Securities-Multi-family [Member]
Assets [Abstract]
Securities available-for-sale	16,655	18,069
Recurring [Member] \| Corporate Debt Securities [Member]
Assets [Abstract]
Securities available-for-sale	1,709	1,704
Recurring [Member] \| Level 1 [Member]
Assets [Abstract]
Securities available-for-sale	1,709	1,704
Equity securities	215	217
Total securities measured at fair value	1,924	1,921
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	1,709	1,704
Recurring [Member] \| Level 2 [Member]
Assets [Abstract]
Securities available-for-sale	105,483	119,102
Equity securities	0	0
Total securities measured at fair value	105,483	119,102
Recurring [Member] \| Level 2 [Member] \| U.S. Government Sponsored Enterprises [Member]
Assets [Abstract]
Securities available-for-sale	5,531	5,531
Recurring [Member] \| Level 2 [Member] \| State and Political Subdivisions [Member]
Assets [Abstract]
Securities available-for-sale	80,438	92,255
Recurring [Member] \| Level 2 [Member] \| Mortgage-backed Securities-Residential [Member]
Assets [Abstract]
Securities available-for-sale	2,859	3,247
Recurring [Member] \| Level 2 [Member] \| Mortgage-backed Securities-Multi-family [Member]
Assets [Abstract]
Securities available-for-sale	16,655	18,069
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 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109979856&loc=d3e26610-111562

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=82897076&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=99377789&loc=d3e19207-110258

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