Fair Value of Financial Instruments - Schedule of Quantitative Information about Level 3 Fair Value Measurements (Detail) - USD ($) $ in Thousands		6 Months Ended	12 Months Ended
		Dec. 31, 2020	Jun. 30, 2020
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Assets, Fair Value		$ 1,696,109	$ 1,385,938
Fair Value, Measurements, Nonrecurring [Member] | Collateral Dependent Loans [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Assets, Fair Value		5,275
Fair Value, Measurements, Nonrecurring [Member] | Collateral Dependent Loans [Member] | Residential Mortgage [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Assets, Fair Value		1,900
Fair Value, Measurements, Nonrecurring [Member] | Collateral Dependent Loans [Member] | Non-Residential Mortgage [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Assets, Fair Value		3,375
Fair Value, Measurements, Nonrecurring [Member] | Collateral Dependent Loans [Member] | Market Valuation of Underlying Collateral [Member] | Adjustments to Reflect Current Conditions or Selling Costs [Member] | Residential Mortgage [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Assets, Fair Value		$ 1,900
Valuation Techniques	[1]	Market valuation of underlying collateral
Unobservable Input	[2]	Adjustments to reflect current conditions/selling costs
Weighted Average		8.50%
Fair Value, Measurements, Nonrecurring [Member] | Collateral Dependent Loans [Member] | Market Valuation of Underlying Collateral [Member] | Adjustments to Reflect Current Conditions or Selling Costs [Member] | Non-Residential Mortgage [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Assets, Fair Value		$ 3,375
Valuation Techniques	[1]	Market valuation of underlying collateral
Unobservable Input	[2]	Adjustments to reflect current conditions/selling costs
Weighted Average		9.93%
Fair Value, Measurements, Nonrecurring [Member] | Collateral Dependent Loans [Member] | Market Valuation of Underlying Collateral [Member] | Minimum [Member] | Adjustments to Reflect Current Conditions or Selling Costs [Member] | Residential Mortgage [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Range		7.00%
Fair Value, Measurements, Nonrecurring [Member] | Collateral Dependent Loans [Member] | Market Valuation of Underlying Collateral [Member] | Minimum [Member] | Adjustments to Reflect Current Conditions or Selling Costs [Member] | Non-Residential Mortgage [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Range		9.00%
Fair Value, Measurements, Nonrecurring [Member] | Collateral Dependent Loans [Member] | Market Valuation of Underlying Collateral [Member] | Maximum [Member] | Adjustments to Reflect Current Conditions or Selling Costs [Member] | Residential Mortgage [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Range		11.00%
Fair Value, Measurements, Nonrecurring [Member] | Collateral Dependent Loans [Member] | Market Valuation of Underlying Collateral [Member] | Maximum [Member] | Adjustments to Reflect Current Conditions or Selling Costs [Member] | Non-Residential Mortgage [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Range		11.00%
Fair Value, Measurements, Nonrecurring [Member] | Other Real Estate Owned [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Assets, Fair Value		$ 178	178
Fair Value, Measurements, Nonrecurring [Member] | Other Real Estate Owned [Member] | Residential Mortgage [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Assets, Fair Value		178	178
Fair Value, Measurements, Nonrecurring [Member] | Other Real Estate Owned [Member] | Market Valuation of Underlying Collateral [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Assets, Fair Value		178	178
Fair Value, Measurements, Nonrecurring [Member] | Other Real Estate Owned [Member] | Market Valuation of Underlying Collateral [Member] | Adjustments to Reflect Current Conditions or Selling Costs [Member] | Residential Mortgage [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Assets, Fair Value		$ 178	$ 178
Valuation Techniques	[3]	Market valuation of underlying collateral	Market valuation of underlying collateral	[1]
Unobservable Input	[2]	Adjustments to reflect current conditions/selling costs	Adjustments to reflect current conditions/selling costs
Range		6.00%
Weighted Average		6.00%	6.00%
Fair Value, Measurements, Nonrecurring [Member] | Other Real Estate Owned [Member] | Market Valuation of Underlying Collateral [Member] | Minimum [Member] | Adjustments to Reflect Current Conditions or Selling Costs [Member] | Residential Mortgage [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Range			6.00%
Fair Value, Measurements, Nonrecurring [Member] | Impaired Loans [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Assets, Fair Value			$ 4,750
Fair Value, Measurements, Nonrecurring [Member] | Impaired Loans [Member] | Residential Mortgage [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Assets, Fair Value			2,339
Fair Value, Measurements, Nonrecurring [Member] | Impaired Loans [Member] | Non-Residential Mortgage [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Assets, Fair Value			2,282
Fair Value, Measurements, Nonrecurring [Member] | Impaired Loans [Member] | Commercial Business [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Assets, Fair Value			129
Fair Value, Measurements, Nonrecurring [Member] | Impaired Loans [Member] | Market Valuation of Underlying Collateral [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Assets, Fair Value			4,750
Fair Value, Measurements, Nonrecurring [Member] | Impaired Loans [Member] | Market Valuation of Underlying Collateral [Member] | Adjustments to Reflect Current Conditions or Selling Costs [Member] | Residential Mortgage [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Assets, Fair Value			$ 2,339
Valuation Techniques	[1]		Market valuation of underlying collateral
Unobservable Input	[2]		Adjustments to reflect current conditions/selling costs
Weighted Average			8.17%
Fair Value, Measurements, Nonrecurring [Member] | Impaired Loans [Member] | Market Valuation of Underlying Collateral [Member] | Adjustments to Reflect Current Conditions or Selling Costs [Member] | Non-Residential Mortgage [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Assets, Fair Value			$ 2,282
Valuation Techniques	[1]		Market valuation of underlying collateral
Unobservable Input	[2]		Adjustments to reflect current conditions/selling costs
Weighted Average			10.27%
Fair Value, Measurements, Nonrecurring [Member] | Impaired Loans [Member] | Market Valuation of Underlying Collateral [Member] | Adjustments to Reflect Current Conditions or Selling Costs [Member] | Commercial Business [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Assets, Fair Value			$ 129
Valuation Techniques	[1]		Market valuation of underlying collateral
Unobservable Input	[2]		Adjustments to reflect current conditions/selling costs
Weighted Average			0.00%
Fair Value, Measurements, Nonrecurring [Member] | Impaired Loans [Member] | Market Valuation of Underlying Collateral [Member] | Minimum [Member] | Adjustments to Reflect Current Conditions or Selling Costs [Member] | Residential Mortgage [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Range			7.00%
Fair Value, Measurements, Nonrecurring [Member] | Impaired Loans [Member] | Market Valuation of Underlying Collateral [Member] | Minimum [Member] | Adjustments to Reflect Current Conditions or Selling Costs [Member] | Non-Residential Mortgage [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Range			9.00%
Fair Value, Measurements, Nonrecurring [Member] | Impaired Loans [Member] | Market Valuation of Underlying Collateral [Member] | Minimum [Member] | Adjustments to Reflect Current Conditions or Selling Costs [Member] | Commercial Business [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Range			0.00%
Fair Value, Measurements, Nonrecurring [Member] | Impaired Loans [Member] | Market Valuation of Underlying Collateral [Member] | Maximum [Member] | Adjustments to Reflect Current Conditions or Selling Costs [Member] | Residential Mortgage [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Range			9.00%
Fair Value, Measurements, Nonrecurring [Member] | Impaired Loans [Member] | Market Valuation of Underlying Collateral [Member] | Maximum [Member] | Adjustments to Reflect Current Conditions or Selling Costs [Member] | Non-Residential Mortgage [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Range			12.00%
Fair Value, Measurements, Nonrecurring [Member] | Impaired Loans [Member] | Market Valuation of Underlying Collateral [Member] | Maximum [Member] | Adjustments to Reflect Current Conditions or Selling Costs [Member] | Commercial Business [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Range			0.00%

[1] The fair value of impaired loans is generally determined based on an independent appraisal of the fair value of a loan’s underlying collateral.

[2] The fair value basis of impaired loans and other real estate owned is adjusted to reflect management’s estimates of selling costs including, but not necessarily limited to, real estate brokerage commissions and title transfer fees

[3] The fair value basis of other real estate owned is generally determined based upon the lower of an independent appraisal of the property’s fair value or the applicable listing price or contracted sales price.