Schedule II -Valuation and Qualifying Accounts (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	$ 831
Balance at End of Period	776	$ 831
Reserve for Uncollectible Accounts Receivable and Sales Return [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	831	530	$ 596
Charged to Costs and Expenses	0	600	215
Deductions	(55)	(300)	(286)
Other	0	1	5
Balance at End of Period	776	831	530
Sales Returns and Allowances [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	1,291	1,291	1,050
Charged to Costs and Expenses	0	0	225
SEC Schedule, 12-09, Valuation Allowances and Reserves, Additions, Charge to Other Account	227
Deductions	0	0	0
Other	0	0	16
Balance at End of Period	1,518	1,291	1,291
Deferred Tax Valuation Allowance [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	8,568	7,312	6,112
Charged to Costs and Expenses	1,420	1,256	1,200
Deductions	(1,800)	0	0
Other	0	0	0
Balance at End of Period	$ 8,188	$ 8,568	$ 7,312