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Subsequent Events - Additional Information (Detail) - USD ($)			3 Months Ended
	Nov. 04, 2020	Nov. 02, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 01, 2020
Subsequent Event [Line Items]
Common stock dividends per share declared			$ 0.09	$ 0.09	$ 0.09	$ 0.09	$ 0.09	$ 0.09
Scenario Forecast [Member]
Subsequent Event [Line Items]
Quarterly dividend payable, aggregate amount subsequent to balance sheet date									$ 4,300,000
Subsequent Event [Member]
Subsequent Event [Line Items]
Dividend declaration date		Nov. 02, 2020
Common stock dividends per share declared		$ 0.09
Dividend record date		Nov. 17, 2020
Dividend payment date		Dec. 01, 2020
Subsequent Event [Member] | Cadence Bank, N.A [Member] | Secured Revolving Credit Facility [Member] | Revolving Credit and Security Agreement (The “Revolving Credit Agreement”) [Member]
Subsequent Event [Line Items]
Secured revolving credit facility amount	$ 10,000,000
Credit agreement maturity period	Nov. 04, 2021
Maximum loan to value ratio percentage	75.00%
Maximum interest rate in no event time	1.50%
Subsequent Event [Member] | Cadence Bank, N.A [Member] | Secured Revolving Credit Facility [Member] | Revolving Credit and Security Agreement (The “Revolving Credit Agreement”) [Member] | Screen Rate [Member]
Subsequent Event [Line Items]
Debt instrument interest over screen rate	1.50%

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