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Securities - Security owned and pledged as collateral (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Jun. 30, 2020
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Security Owned and Pledged as Collateral, Fair Value | $ 150,300 | $ 156,100
State and political subdivisions |  |
Security Owned and Pledged as Collateral, Fair Value | 34,900 | 32,000
Mortgage-backed securities |  |
Security Owned and Pledged as Collateral, Fair Value | 85,500 | 82,000
Collateralized Mortgage Obligations |  |
Security Owned and Pledged as Collateral, Fair Value | 28,900 | 41,900
Other securities |  |
Security Owned and Pledged as Collateral, Fair Value | $ 1,000 | $ 200

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