Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Shareholders' Equity - Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Oct. 08, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, amount recognized	$ 0	$ 0	$ 0	$ 28,000
Options granted	0		0
Stock repurchased during period, value		$ 6,000
Stock repurchased during period, shares			3,814
2019-2020 Common Share Repurchase Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock repurchased during period, value				$ 4,000
Stock repurchased during period, shares				3,814
Maximum [Member] \| 2019-2020 Common Share Repurchase Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Amount of shares authorized to be repurchased					$ 750,000
2011 Director Stock Option Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted				50,000