Date of signing land use right assignment contract.

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Share based compensation arrangement by share based payment award award vesting date.

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Area of land held.

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Contractual interest rate for funds borrowed, under the debt agreement.

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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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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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The cash outflow from the acquisition of real estate intended to generate income for the owner; excludes land acquired for use by the owner.

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Date the equity-based award expires, in CCYY-MM-DD format.

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Gross number of share options (or share units) granted during the period.

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No definition available.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Purchase price of common stock expressed as a percentage of its fair value.

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Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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Subsequent Events - Additional Information (Detail) $ / shares in Units, ¥ in Thousands			1 Months Ended	12 Months Ended
	Mar. 19, 2020 USD ($) m²	Mar. 19, 2020 CNY (¥) m²	Jan. 31, 2020 USD ($) $ / shares shares	Dec. 31, 2019 USD ($) $ / shares	Dec. 31, 2018 $ / shares	Dec. 31, 2017 $ / shares	Feb. 27, 2020 USD ($)	Feb. 13, 2020 USD ($)	Jan. 19, 2020 USD ($)	Oct. 31, 2019 USD ($)	Sep. 30, 2019 USD ($)
Subsequent Event [Line Items]
Exercise price of stock options granted \| $ / shares				$ 6.29	$ 6.22	$ 6.25
Subsequent Event
Subsequent Event [Line Items]
Aggregate stock options granted \| shares			1,825,000
Exercise price of stock options granted \| $ / shares			$ 9.41
Percentage of stock options granted			10000.00%
Subsequent Event \| Guangdong Province
Subsequent Event [Line Items]
Area of land \| m²	33,763	33,763
Total consideration of land parcel	$ 101,070,000	¥ 705,480
Land use right assignment contract	Mar. 31, 2020	Mar. 31, 2020
Subsequent Event \| Ying Chi Kwok
Subsequent Event [Line Items]
Aggregate stock options granted \| shares			900,000
Subsequent Event \| Yu Zhang
Subsequent Event [Line Items]
Aggregate stock options granted \| shares			200,000
Subsequent Event \| Share-based Compensation Award, Tranche One
Subsequent Event [Line Items]
Vesting date of options			Jan. 22, 2020
Expiration date of options			Dec. 31, 2020
Subsequent Event \| Share-based Compensation Award, Tranche Two
Subsequent Event [Line Items]
Vesting date of options			Jan. 22, 2021
Expiration date of options			Dec. 31, 2021
Subsequent Event \| Share-based Compensation Award, Tranche Three
Subsequent Event [Line Items]
Vesting date of options			Jan. 22, 2022
Expiration date of options			Dec. 31, 2022
Subsequent Event \| Share Based Compensation Award Tranche Four
Subsequent Event [Line Items]
Vesting date of options			Jan. 22, 2023
Expiration date of options			Dec. 31, 2023
Subsequent Event \| Share Based Compensation Award Tranche Five
Subsequent Event [Line Items]
Vesting date of options			Jan. 22, 2024
Expiration date of options			Dec. 31, 2024
Bank of China \| Zastron Electronic (Shenzhen) Co., Ltd. (Zastron Shenzhen) \| Nam Tai Inno Park
Subsequent Event [Line Items]
Line of credit, current											$ 73,050,000
Line of credit, maximum borrowing capacity				$ 143,000,000							$ 143,000,000
Bank of China \| Zastron Electronic (Shenzhen) Co., Ltd. (Zastron Shenzhen) \| Nam Tai Inno Park \| Subsequent Event
Subsequent Event [Line Items]
Line of credit, current									$ 3,060,000
Shenzhen Rural Commercial Bank \| Nam Tai Investment (Shenzhen) Co., Ltd. \| Nam Tai Technology Center
Subsequent Event [Line Items]
Line of credit, current										$ 12,030,000
Line of credit, maximum borrowing capacity										$ 143,000,000
Shenzhen Rural Commercial Bank \| Nam Tai Investment (Shenzhen) Co., Ltd. \| Nam Tai Technology Center \| Subsequent Event
Subsequent Event [Line Items]
Line of credit, current							$ 7,540,000		$ 9,080,000
Xiamen International Bank \| Zastron Electronic (Shenzhen) Co., Ltd. (Zastron Shenzhen) \| Subsequent Event
Subsequent Event [Line Items]
Line of credit, current								$ 15,760,000
Line of credit, maximum borrowing capacity			$ 15,760,000
Debt instrument, interest rate			7.40%