Intangible Assets, Net - Additional Information (Detail) - USD ($) $ in Thousands  | 
3 Months Ended | 12 Months Ended | |
|---|---|---|---|
Mar. 31, 2021  | 
Mar. 31, 2020  | 
Dec. 31, 2020  | 
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| Amortization expenses of intangible assets | $ 657 | $ 703 | $ 2,733 | 
| Intangible assets wrote off due to disposal | 6 | ||
| Accumulated amortization of intangible assets related to disposal | $ 6 | ||
| Non-compete Agreement [Member] | |||
| Intangible assets wrote off due to disposal | 6 | ||
| Accumulated amortization of intangible assets related to disposal | $ 5 | ||
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- Definition Amortization of intangible assets written off due to disposal. No definition available. 
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- Definition Finite-lived intangible assets, written off due to disposal. No definition available. 
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- Definition The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Details 
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