Segment Information - Continuing Operations by Reportable Segment (Detail) $ in Thousands	3 Months Ended
Mar. 31, 2022 USD ($) segment	Mar. 31, 2021 USD ($)
Segment Reporting [Abstract]
Number of reportable segments \| segment	2
Number of operating segments \| segment	2
Segment Reporting Information [Line Items]
Net sales	$ 128,067	$ 126,804
Income (loss) from operations	(3,420)	978
Interest expense	(3,439)	(2,024)
Other	2,996	(6,018)
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest	(3,863)	(7,064)
United States and Puerto Rico
Segment Reporting Information [Line Items]
Net sales	78,282	77,197
Operating Segments \| Mobile Solutions
Segment Reporting Information [Line Items]
Net sales	76,070	77,776
Income (loss) from operations	1,969	6,090
Operating Segments \| Mobile Solutions \| United States and Puerto Rico
Segment Reporting Information [Line Items]
Net sales	37,810	37,438
Operating Segments \| Power Solutions
Segment Reporting Information [Line Items]
Net sales	52,011	49,075
Income (loss) from operations	364	2,432
Operating Segments \| Power Solutions \| United States and Puerto Rico
Segment Reporting Information [Line Items]
Net sales	40,486	39,806
Corporate and Eliminations
Segment Reporting Information [Line Items]
Income (loss) from operations	(5,753)	(7,544)
Intersegment Sales Eliminations
Segment Reporting Information [Line Items]
Net sales	(14)	(47)
Intersegment Sales Eliminations \| United States and Puerto Rico
Segment Reporting Information [Line Items]
Net sales	$ (14)	$ (47)

Gain (loss) on derivatives and other non-operating income (expense) net.

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Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

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Amount of the cost of borrowed funds accounted for as interest expense.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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