Benefit Plans - Schedule of Expected Benefit Payments (Details) $ in Thousands	Jun. 30, 2023 USD ($)
Atlas Bank Retirement Income Plan ("ABRIP")
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
2024	$ 146
2025	147
2026	148
2027	145
2028	140
2029-2033	637
Benefit Equalization Plan ("BEP")
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
2024	241
2025	237
2026	232
2027	227
2028	221
2029-2033	999
Postretirement Welfare Plan
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
2024	54
2025	62
2026	74
2027	82
2028	99
2029-2033	580
Directors' Consultation and Retirement Plan ("DCRP")
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
2024	72
2025	118
2026	138
2027	157
2028	176
2029-2033	1,301
Supplemental Executive Retirement Plan (SERP)
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
2024	0
2025	0
2026	0
2027	0
2028	0
2029-2033	$ 633

Amount of benefit for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following current fiscal year.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

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Amount of benefit for defined benefit plan expected to be paid in next fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in fifth fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in fourth fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in third fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in second fiscal year following current fiscal year.

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