Face (par) amount of debt instrument at time of issuance.

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- Definition

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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No definition available.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

The carrying value as of the balance sheet date of the current portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of loans from a bank with maturities initially due after one year or beyond the normal operating cycle if longer.

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- Definition

The carrying amount, as of the date of the latest financial statement presented, of real estate owned but transferred to serve as collateral for the payment of the related debt obligation, primarily a secured borrowing or repurchase agreement, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

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- Definition

Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Bank Loans and Banking Facilities - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2020	Feb. 29, 2020	Dec. 31, 2019	Oct. 31, 2019	Sep. 30, 2019	Aug. 31, 2019
Debt Instrument [Line Items]
Bank borrowings	$ 72,330,000
Repayments of principal	54,870,000
Line of credit financing cost	276,000		$ 412,000
Assets pledged to banks	277,800,000		$ 81,700,000
Nam Tai Investment (Shenzhen) Co., Ltd. \| Bank of Beijing
Debt Instrument [Line Items]
Repayments of principal	500,000
Line of credit, current						$ 7,160,000
Line of credit, maximum borrowing capacity						7,160,000
Line of credit financing cost						$ 290,000
Nam Tai Investment (Shenzhen) Co., Ltd. \| Shenzhen Rural Commercial Bank \| Nam Tai Technology Center
Debt Instrument [Line Items]
Repayments of principal	29,000,000.0
Line of credit, current				$ 16,820,000
Line of credit, maximum borrowing capacity				143,000,000
Nam Tai Investment (Shenzhen) Co., Ltd. \| China Everbright Bank \| Nam Tai Technology Center
Debt Instrument [Line Items]
Repayments of principal	1,450,000
Line of credit, current				1,430,000
Line of credit, maximum borrowing capacity				1,430,000
Line of credit financing cost				30,000.00
Zastron Electronic (Shenzhen) Co., Ltd. (Zastron Shenzhen) \| Bank of China \| Nam Tai Inno Park
Debt Instrument [Line Items]
Repayments of principal	23,150,000
Line of credit, current	39,560,000
Line of credit, maximum borrowing capacity					$ 143,000,000
Zastron Electronic (Shenzhen) Co., Ltd. (Zastron Shenzhen) \| Xiamen International Bank \| Nam Tai Inno Park
Debt Instrument [Line Items]
Repayments of principal	480,000
Line of credit, current	15,950,000
Line of credit, maximum borrowing capacity		$ 15,950,000
Debt Instrument, Face Amount		$ 15,950,000
Nam Tai (Shenzhen) Technology Park Operations Management Co., Ltd (“NTTP”) \| Industrial Bank \| Nam Tai Inno Valley
Debt Instrument [Line Items]
Repayments of principal	$ 290,000
Line of credit, current				4,300,000
Line of credit, maximum borrowing capacity				4,300,000
Line of credit financing cost				$ 170,000