Loans and Allowance for Credit Losses - Collateral dependent loans and related ACL (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Jun. 30, 2020
Related allowance for credit losses	$ 35,227	$ 25,139
Residential
Related allowance for credit losses		$ 4,875
Residential \| Collateral-dependent Loans
Amortized cost	904
Related allowance for credit losses	232
1- to 4-family residential loans \| Collateral-dependent Loans
Amortized cost	904
Related allowance for credit losses	$ 232

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Name:	us-gaap_FinancingReceivableAllowanceForCreditLosses
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant