Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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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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No definition available.

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Number of shares authorized for issuance under share-based payment arrangement.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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Represents the number of shares originally approved (usually by shareholders and board of directors) for awards under the prior plan of equity based compensation transferred to the current plan.

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Represents the number of shares reserved for issuance under stock plans that validly exist and are outstanding as of the balance sheet date.

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ORDINARY SHARE AND SHARE INCENTIVE PLANS - Stock Incentive Plans - Additional Information (Details) - shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2016
2017 Equity Incentive Plan
Stock Incentive Plans
Number of shares authorized		2,000,000
Number of ordinary shares available for issuance pursuant to future grants	1,389,260
Number of shares transferred from the prior plan	1,590,693
2017 Equity Incentive Plan \| Maximum
Stock Incentive Plans
Vesting period	4 years
2017 Equity Incentive Plan \| Minimum
Stock Incentive Plans
Vesting period	2 years
2017 Equity Incentive Plan \| Stock Options and Restricted Stock Units RSU
Stock Incentive Plans
Number of awards outstanding (in shares)	1,478,181
2006 Equity Incentive Plan
Stock Incentive Plans
Number of shares expired	1,590,693