Goodwill and Other Intangible Assets - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Finite Lived Intangible Assets [Line Items]
Change in goodwill	$ 0	$ 0
Goodwill	3,332,000	3,332,000
Amortization Of Intangible Assets	144,000	885,000
Continuing Operations [Member]
Finite Lived Intangible Assets [Line Items]
Amortization Of Intangible Assets	100,000	900,000
Operating Expense [Member]
Finite Lived Intangible Assets [Line Items]
Amortization Of Intangible Assets		200,000
Cost of Revenues [Member]
Finite Lived Intangible Assets [Line Items]
Amortization Of Intangible Assets	$ 100,000	$ 700,000
Minimum [Member]
Finite Lived Intangible Assets [Line Items]
Amortization of intangible assets basis over estimated useful lives	1 year
Maximum [Member]
Finite Lived Intangible Assets [Line Items]
Amortization of intangible assets basis over estimated useful lives	6 years