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Cash Flow Statement - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Interest paid			$ 9	$ 9
Income taxes paid			51	27
Issuance of treasury stock	$ 87	$ 49
Capital expenditures			37	10
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of treasury stock			$ 87	$ 49

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Future cash outflow to pay for purchases of fixed assets that have occurred.

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

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