Loans Receivable - Schedule of Modified Non-TDR Loans by Loan Segments (Detail) $ in Thousands	6 Months Ended
	Dec. 31, 2020 USD ($) Loan	[1]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Loans | Loan	37
Balance | $	$ 33,177
Home Equity Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Loans | Loan	1
Balance | $	$ 39
Commercial Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Loans | Loan	16
Balance | $	$ 25,474
Non-Residential Mortgage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Loans | Loan	2
Balance | $	$ 5,913
Commercial Business [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Loans | Loan	5
Balance | $	$ 1,314
One-to Four-Family Residential Mortgage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Loans | Loan	20
Balance | $	$ 7,664
Multi-Family Mortgage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Loans | Loan	9
Balance | $	$ 18,247

[1] Includes loans acquired in conjunction with the Company’s acquisition of MSB on July 10, 2020.