Investment Securities - Investment Securities with Fair Value and Unrealized Losses (Detail) - USD ($) $ in Thousands	Mar. 31, 2022	Jun. 30, 2021
Schedule of Investments [Line Items]
Available for sale, Less than 12 months, Fair Value	$ 20,148	$ 27,416
Available for sale, Less than 12 months, Unrealized/Unrecognized Loss	(1,494)	(373)
Available for sale, 12 months or greater, Fair Value	11,455	1,339
Available for sale, 12 months or greater, Unrealized/Unrecognized Loss	(1,726)	(10)
Available for sale, Total, Fair Value	31,603	28,755
Available for sale, Total, Unrealized/Unrecognized Loss	(3,220)	(383)
Held to maturity, Less than 12 months, Fair Value	308,662	134,925
Held to maturity, Less than 12 months, Unrealized/ Unrecognized Loss	(27,244)	(1,402)
Held to maturity, 12 months or greater, Fair Value	36,187	4,975
Held to maturity, 12 months or greater, Unrealized/ Unrecognized Loss	(4,919)	(25)
Held to maturity, Total, Fair Value	344,849	139,900
Held to maturity, Total, Unrealized/ Unrecognized Loss	(32,163)	(1,427)
U.S. Government and Agency Obligations [Member]
Schedule of Investments [Line Items]
Available for sale, Less than 12 months, Fair Value	10,229	14,811
Available for sale, Less than 12 months, Unrealized/Unrecognized Loss	(710)	(121)
Available for sale, Total, Fair Value	10,229	14,811
Available for sale, Total, Unrealized/Unrecognized Loss	(710)	(121)
Held to maturity, Less than 12 months, Fair Value	37,198	19,409
Held to maturity, Less than 12 months, Unrealized/ Unrecognized Loss	(1,801)	(84)
Held to maturity, 12 months or greater, Fair Value	2,807
Held to maturity, 12 months or greater, Unrealized/ Unrecognized Loss	(188)
Held to maturity, Total, Fair Value	40,005	19,409
Held to maturity, Total, Unrealized/ Unrecognized Loss	(1,989)	(84)
State and Municipal [Member]
Schedule of Investments [Line Items]
Available for sale, Less than 12 months, Fair Value	3,312	2,990
Available for sale, Less than 12 months, Unrealized/Unrecognized Loss	(710)	(30)
Available for sale, 12 months or greater, Fair Value	2,221
Available for sale, 12 months or greater, Unrealized/Unrecognized Loss	(797)
Available for sale, Total, Fair Value	5,533	2,990
Available for sale, Total, Unrealized/Unrecognized Loss	(1,507)	(30)
Held to maturity, Less than 12 months, Fair Value	68,772	19,980
Held to maturity, Less than 12 months, Unrealized/ Unrecognized Loss	(14,064)	(248)
Held to maturity, 12 months or greater, Fair Value	3,341
Held to maturity, 12 months or greater, Unrealized/ Unrecognized Loss	(1,230)
Held to maturity, Total, Fair Value	72,113	19,980
Held to maturity, Total, Unrealized/ Unrecognized Loss	(15,294)	(248)
Mortgage-backed Securities - Residential [Member]
Schedule of Investments [Line Items]
Available for sale, Less than 12 months, Fair Value	1,234	9,615
Available for sale, Less than 12 months, Unrealized/Unrecognized Loss	(12)	(222)
Available for sale, 12 months or greater, Fair Value	9,234	1,339
Available for sale, 12 months or greater, Unrealized/Unrecognized Loss	(929)	(10)
Available for sale, Total, Fair Value	10,468	10,954
Available for sale, Total, Unrealized/Unrecognized Loss	(941)	(232)
Held to maturity, Less than 12 months, Fair Value	90,221	30,335
Held to maturity, Less than 12 months, Unrealized/ Unrecognized Loss	(4,751)	(107)
Held to maturity, 12 months or greater, Fair Value	4,410
Held to maturity, 12 months or greater, Unrealized/ Unrecognized Loss	(407)
Held to maturity, Total, Fair Value	94,631	30,335
Held to maturity, Total, Unrealized/ Unrecognized Loss	(5,158)	(107)
Corporate [Member]
Schedule of Investments [Line Items]
Available for sale, Less than 12 months, Fair Value	2,970
Available for sale, Less than 12 months, Unrealized/Unrecognized Loss	(30)
Available for sale, Total, Fair Value	2,970
Available for sale, Total, Unrealized/Unrecognized Loss	(30)
Held to maturity, Less than 12 months, Fair Value	40,483	2,488
Held to maturity, Less than 12 months, Unrealized/ Unrecognized Loss	(2,075)	(13)
Held to maturity, 12 months or greater, Fair Value		4,975
Held to maturity, 12 months or greater, Unrealized/ Unrecognized Loss		(25)
Held to maturity, Total, Fair Value	40,483	7,463
Held to maturity, Total, Unrealized/ Unrecognized Loss	(2,075)	(38)
Mortgage-backed Securities - Collateralized Mortgage Obligations [Member]
Schedule of Investments [Line Items]
Held to maturity, Less than 12 months, Fair Value	13,899	15,133
Held to maturity, Less than 12 months, Unrealized/ Unrecognized Loss	(540)	(328)
Held to maturity, 12 months or greater, Fair Value	7,483
Held to maturity, 12 months or greater, Unrealized/ Unrecognized Loss	(833)
Held to maturity, Total, Fair Value	21,382	15,133
Held to maturity, Total, Unrealized/ Unrecognized Loss	(1,373)	(328)
Mortgage-backed Securities - Commercial [Member]
Schedule of Investments [Line Items]
Available for sale, Less than 12 months, Fair Value	2,403
Available for sale, Less than 12 months, Unrealized/Unrecognized Loss	(32)
Available for sale, Total, Fair Value	2,403
Available for sale, Total, Unrealized/Unrecognized Loss	(32)
Held to maturity, Less than 12 months, Fair Value	58,089	47,580
Held to maturity, Less than 12 months, Unrealized/ Unrecognized Loss	(4,013)	(622)
Held to maturity, 12 months or greater, Fair Value	18,146
Held to maturity, 12 months or greater, Unrealized/ Unrecognized Loss	(2,261)
Held to maturity, Total, Fair Value	76,235	47,580
Held to maturity, Total, Unrealized/ Unrecognized Loss	$ (6,274)	$ (622)

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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