Accounts Receivable, Net - Schedule of Accounts Receivable, Net (Detail) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Accounts Notes And Loans Receivable [Line Items]
Allowance for doubtful accounts	$ (70)	$ (70)
Total accounts receivable, net	14,904	12,140
Security Products
Accounts Notes And Loans Receivable [Line Items]
Accounts receivable, gross	12,622	10,596
Marine Components
Accounts Notes And Loans Receivable [Line Items]
Accounts receivable, gross	$ 2,352	$ 1,614

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.

No definition available.

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- Definition

For unclassified balance sheet, amounts due from customers or clients for goods or services that have been delivered or sold in the normal course of business.

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- Definition

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

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- Definition

For an unclassified balance sheet, a valuation allowance for receivables due a company that are expected to be uncollectible.

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