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Impairment of Securities - Schedule of Temporary Impairment Losses, Investments (Detail) $ in Thousands | Sep. 30, 2019 USD ($) Security | Jun. 30, 2019 USD ($) Security
--- | --- | ---
Schedule Of Held To Maturity Securities [Line Items] |  |  |
Less than 12 Months: Fair Value |  | $ 2,975 | $ 712
Less than 12 Months: Unrecognized Losses |  | 6 | 2
12 Months or More: Fair Value |  | 470 | 95,196
12 Months or More: Unrecognized Losses |  | $ 1 | $ 706
Number of Securities | Security |  | 10 | 96
Total: Fair Value |  | $ 3,445 | $ 95,908
Total: Unrecognized Losses |  | 7 | 708
Debt Securities [Member] |  |  |
Schedule Of Held To Maturity Securities [Line Items] |  |  |
Total: Unrecognized Losses |  | 7 | 16
Debt Securities [Member] | Obligations of State and Political Subdivisions [Member] |  |  |
Schedule Of Held To Maturity Securities [Line Items] |  |  |
Less than 12 Months: Fair Value |  | 2,975 | 274
Less than 12 Months: Unrecognized Losses |  | 6 | 1
12 Months or More: Fair Value |  | 470 | 7,149
12 Months or More: Unrecognized Losses |  | $ 1 | $ 15
Number of Securities | Security |  | 10 | 19
Total: Fair Value |  | $ 3,445 | $ 7,423
Total: Unrecognized Losses |  | $ 7 | 16
Collateralized Mortgage Obligations Excluding Pass Through Securities [Member] |  |  |
Schedule Of Held To Maturity Securities [Line Items] |  |  |
12 Months or More: Fair Value |  |  | 9,347
12 Months or More: Unrecognized Losses |  |  | $ 168
Number of Securities | Security |  |  | 5
Total: Fair Value |  |  | $ 9,347
Total: Unrecognized Losses | [1] |  | 168
Residential Pass-Through Securities [Member] |  |  |
Schedule Of Held To Maturity Securities [Line Items] |  |  |
Less than 12 Months: Fair Value |  |  | 438
Less than 12 Months: Unrecognized Losses |  |  | 1
12 Months or More: Fair Value |  |  | 76,848
12 Months or More: Unrecognized Losses |  |  | $ 517
Number of Securities | Security |  |  | 70
Total: Fair Value |  |  | $ 77,286
Total: Unrecognized Losses | [1] |  | 518
Commercial Pass-Through Securities [Member] |  |  |
Schedule Of Held To Maturity Securities [Line Items] |  |  |
12 Months or More: Fair Value |  |  | 1,852
12 Months or More: Unrecognized Losses |  |  | $ 6
Number of Securities | Security |  |  | 2
Total: Fair Value |  |  | $ 1,852
Total: Unrecognized Losses | [1] |  | $ 6
[1] | Government-sponsored enterprises.

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