Summary of Significant Accounting Policies - Additional Information (Detail)					3 Months Ended				9 Months Ended		12 Months Ended
	Sep. 10, 2020	Jul. 06, 2020 USD ($) $ / shares shares	Jan. 28, 2020	Jul. 24, 2018	Sep. 26, 2020 USD ($) shares	Mar. 28, 2020 USD ($)	Dec. 31, 2019 USD ($)	Sep. 28, 2019 USD ($) shares	Sep. 26, 2020 USD ($) shares	Sep. 28, 2019 USD ($) shares	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Accumulated deficit					$ 331,402,000		$ 328,973,000		$ 331,402,000		$ 328,973,000
Incurred net loss					(606,000)			$ (2,375,000)	(2,429,000)	$ (7,301,000)	9,200,000
Negative cash flows from operations									(2,652,000)	(6,762,000)	8,800,000
Cash and cash equivalents					1,762,000		713,000	$ 275,000	1,762,000	$ 275,000	713,000	$ 5,616,000
Reverse split	1-for-10			1-for-10
Reverse split conversion ratio	0.1
Finance leases					0				0
Inventory, net					68,000		263,000		$ 68,000		263,000
Minimum percentage of tax benefit realized									50.00%
Liabilities for uncertain tax positions					0				$ 0
Interest or penalties on uncertain tax positions									$ 0
U.S. statutory corporate tax rate									21.00%
Deferred tax assets					$ 0		0		$ 0		0
Stock options granted during the period | shares					0			0	0	0
Warrants Exercise									$ 2,479,000
Percentage of Cost Reduction Employee Workforce			70.00%
Net cash proceedsfrom the sale of our common and preferred shares and warrants											3,900,000
Wire inventory expensed						$ 190,000			190,000	$ 0
Gain on sale of production wire equipment						510,000			$ 510,000	$ 0
Common stock issued | shares		400,000
Preferred equity interest, value		$ 1,600,000
Purchase price | $ / shares		$ 4.00
Warrants [Member]
Summary Of Significant Accounting Policies [Line Items]
Warrant exercises, Shares | shares									978,594
Warrants Exercise					$ 2,000,000,000		99,000		$ 2,500,000
Furniture and Fixtures [Member]
Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment useful life									7 years
Patents and Licenses [Member]
Summary Of Significant Accounting Policies [Line Items]
Estimated useful lives									17 years
Impairment of Intangible Assets						$ 134,000			$ 0
Minimum [Member] | Equipment [Member]
Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment useful life									3 years
Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Term of lease					12 months				12 months
Maximum [Member] | Equipment [Member]
Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment useful life									5 years
State [Member]
Summary Of Significant Accounting Policies [Line Items]
Open tax year									2013
State [Member] | Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Reduction of taxable income											17,900,000
Federal [Member]
Summary Of Significant Accounting Policies [Line Items]
Open tax year									2014
Net operating loss carryforwards							$ 342.4				$ 342.4
Earliest Tax Year [Member]
Summary Of Significant Accounting Policies [Line Items]
Operating loss carryforwards expiration period									2020
Latest Tax Year [Member]
Summary Of Significant Accounting Policies [Line Items]
Operating loss carryforwards expiration period									2038