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Fair Value of Financial Instruments - Schedule of Assets Measured At Fair Value on a Non-recurring Basis (Detail) - USD ($) $ in Thousands | Sep. 30, 2019 | Jun. 30, 2019
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Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value | $ 1,234,121 | $ 718,119
Fair Value, Measurements, Nonrecurring [Member] | Impaired Loans [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value | 3,975 | 3,878
Fair Value, Measurements, Nonrecurring [Member] | Impaired Loans [Member] | Residential Mortgage [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value | 3,157 | 3,071
Fair Value, Measurements, Nonrecurring [Member] | Impaired Loans [Member] | Non-Residential Mortgage [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value | 791 | 791
Fair Value, Measurements, Nonrecurring [Member] | Impaired Loans [Member] | Commercial Business [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value | 27 | 16
Significant Other Observable Inputs (Level 2) [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value | 1,233,121 | 717,119
Significant Unobservable Inputs (Level 3) [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value | 1,000 | 1,000
Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member] | Impaired Loans [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value | 3,975 | 3,878
Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member] | Impaired Loans [Member] | Residential Mortgage [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value | 3,157 | 3,071
Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member] | Impaired Loans [Member] | Non-Residential Mortgage [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value | 791 | 791
Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member] | Impaired Loans [Member] | Commercial Business [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value | $ 27 | $ 16

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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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