Condensed Consolidated Statements of Comprehensive Income (Loss) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020
Statement of Comprehensive Income [Abstract]
Unrealized appreciation (depreciation) on available-for-sale securities, net of taxes	$ 1,025	$ 705	$ 1,078	$ 852
Less: reclassification adjustment for realized gains included in net income, net of taxes	33	42	91	40
Postretirement health plan amortization of transition obligation and prior service cost and change in net loss, tax	$ 3	$ 1	$ 6	$ 5

Amount of tax expense (benefit), after reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities, attributable to parent entity. Excludes amounts related to other than temporary impairment (OTTI) loss.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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