Contingency (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Sep. 30, 2019	Mar. 28, 2018
Commitments and Contingencies Disclosure [Abstract]
Sales tax examination excluding penalties and interest accrued				$ 824
Sales tax examination penalties and interest accrued				339
Sales tax examination liability refund adjustment from settlement with tax authority	$ 60			$ 1,163
Sales tax contingent liabilities		$ 96	$ 150
Sales tax examination, payments	15	$ 50
Sales tax examination, interest	5
Sales tax examination, reversed expense	$ 181