Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Income Taxes [Line Items]
Valuation allowance	$ 17,853				$ 18,204				$ 17,853	$ 18,204
Net operating losses	489	$ 368	$ (2,220)	$ (3,265)	$ (2,569)	$ (3,900)	$ (4,287)	$ (6,448)	$ (4,628)	$ (17,204)
Operating loss, expiration date									2037
Federal [Member]
Income Taxes [Line Items]
Net operating loss carryforwards	92,400								$ 92,400
Net operating losses									28,700
State [Member]
Income Taxes [Line Items]
Net operating loss carryforwards	$ 24,900								$ 24,900