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Stock-Based Compensation - Additional Information (Detail) - USD ($)			3 Months Ended		9 Months Ended
	Dec. 03, 2019	Jul. 25, 2019	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Special cash dividend paid	$ 6,700,000	$ 20,000,000.0			$ 20,000,000.0
Dividend payable date	Dec. 23, 2019	Sep. 05, 2019			Sep. 05, 2019
Dividend payable, date of record	Dec. 16, 2019	Aug. 28, 2019			Aug. 28, 2019
Incremental compensation expense					$ 0
Additional compensation expense					$ 0
Weighted-average grant date fair value per share of stock options			$ 1.90	$ 3.53	$ 1.90	$ 3.53
Stock Incentive Plan 2011 [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares of common stock available for grant (in shares)			1,500,000		1,500,000
Number of Options, Granted			22,000		22,000