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Borrowings - Additional Information (Detail) - USD ($) $ in Millions | Sep. 30, 2019 | Jun. 30, 2019
--- | --- | ---
Debt Instrument [Line Items] |  |
Other borrowings, sweep accounts | $ 7.5 | $ 8.8
Borrowings for liquidity management purposes | 0.0 | 30.0
Mortgage-Backed Securities [Member] |  |
Debt Instrument [Line Items] |  |
Federal Home Loan Bank, advances, general debt obligations, disclosures, collateral pledged | 158.7 | 160.8
Investment in Federal Home Loan Bank Stock [Member] |  |
Debt Instrument [Line Items] |  |
Federal Home Loan Bank, advances, general debt obligations, disclosures, collateral pledged | $ 3,010.0 | $ 3,040.0

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- Definition Amount of the collateral pledged in support of federal home loan bank advances outstanding. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 50 -Paragraph 3 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822 + Details
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- Definition Amount of borrowings classified as other, maturing within one year or the normal operating cycle, if longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(a)(7)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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