Borrowings - Schedule of Fixed Rate Advances from FHLB (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Jun. 30, 2018
Debt Instrument [Line Items]
Federal Home Loan Bank, Advances, Balance, Less than one year	$ 866,500	$ 741,000
Federal Home Loan Bank, Advances, Balance Due in One to two years	30,300	48,400
Federal Home Loan Bank, Advances, Balance Due in two to three years	109,904	64,160
Federal Home Loan Bank, Advances, Balance Due in three to four years	15,000	35,700
Federal Home Loan Bank, Advances, Balance Due in four to five years	145,000	155,000
Federal Home Loan Bank, Advances, Balance greater than five years	132,500	132,500
Federal Home Loan Bank, Advances, Total	1,299,204	1,176,760
Federal Home Loan Bank, Advances, Unamortized Fair Value Adjustments	(5,359)	(6,616)
Total Federal Home Loan Bank, Advances, After Fair Value Adjustments	$ 1,293,845	$ 1,170,144
Federal Home Loan Bank, Advances, Weighted Average Interest Rate, Due in less than one year	2.61%	2.09%
Federal Home Loan Bank, Advances, Weighted Average Interest Rate, Due in one to two years	1.79%	1.66%
Federal Home Loan Bank, Advances, Weighted Average Interest Rate, Due in two to three years	2.18%	1.88%
Federal Home Loan Bank, Advances, Weighted Average Interest Rate, Due in three to four years	2.49%	2.17%
Federal Home Loan Bank, Advances, Weighted Average Interest Rate, Due in four to five years	3.04%	3.00%
Federal Home Loan Bank, Advances, Weighted Average Interest Rate, Due in greater than five years	2.68%	2.68%
Weighted Average [Member]
Debt Instrument [Line Items]
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Weighted Average Interest Rate	2.61%	2.25%

Federal home loan bank advances after fair value adjustments.

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Federal home loan bank advances unamortized fair value adjustments.

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Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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States the interest rate applicable to Federal Home Loan Bank advances outstanding as of the Balance Sheet date.

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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due after five years of the Balance Sheet date.

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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due from four to five years of the Balance Sheet date.

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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due within one year of the Balance Sheet date.

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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due from one to two years of the Balance Sheet date.

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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due from three to four years of the Balance Sheet date.

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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due from two to three years of the Balance Sheet date.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the remainder of the fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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