Compensation Related Costs Share Based Payments Disclosure [Line Items]

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Limit of Shares Issued or To Be Issued Pursuant to Options Granted

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- Definition

Share Based Compensation Arrangement by Share Based Payment Award, Options, Grants in Period, Weighted Average Option Price

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Option Price

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Section 50
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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

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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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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- Definition

The highest quantity of shares an employee can purchase under the plan per period.

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- Definition

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

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- Definition

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

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- Definition

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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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

Maximum number of shares that may be issued in accordance with the plan as a proportion of outstanding capital stock.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

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

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Share-based awards - Narrative (Details) - USD ($)						6 Months Ended		12 Months Ended
Share-based awards - Narrative (Details) - USD ($)	Jun. 30, 2021	Dec. 31, 2020	Feb. 14, 2017	May 11, 2015	Jan. 17, 2003	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020	May 16, 2019	Feb. 13, 2017
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Non-cash stock compensation expense not yet recognized	$ 72,600,000					$ 72,600,000
Unrecognized stock-based compensation expense, weighted average period	2 years 5 months 1 day
Consultants Stock Plan, 2008 Plan
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Ordinary shares which have been reserved for issuance (in shares)			1,000,000.0							400,000
Limit of shares issued or to be issued pursuant to options granted (in shares)			1,000,000.0
Employee Stock Plan, 2008 Plan
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Ordinary shares which have been reserved for issuance (in shares)			6,000,000.0
Maximum number of shares per employee (in shares)			400,000
Option Plans 2008 \| Minimum
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Percentage of option price for fair value of ordinary share (percentage)			100.00%
Employee Stock Plan, 2003 Plan
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Ordinary shares which have been reserved for issuance (in shares)					6,000,000.0
Maximum number of shares per employee (in shares)					400,000
Maximum number of award as percentage of shares outstanding (percentage)					10.00%
Employee Stock Option
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Weighted average contractual term of options outstanding	4 years 10 months 24 days	4 years 10 months 9 days
Weighted average fair value per option (USD per share)						$ 25.97
Exercisable - number of shares (in shares)	336,942					336,942
Exercisable - weighted average remaining contractual life	3 years 7 months 17 days
Exercisable - weighted average exercise price (USD per share)	$ 92.71					$ 92.71
Fully vested total intrinsic value	$ 38,400,000					$ 38,400,000
Intrinsic value of option exercised						$ 700,000	$ 4,300,000
Employee Stock Option \| Award Date, All years excluding 2018
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Shares vesting period						5 years
Shares expiration period						8 years
Employee Stock Option \| Non-executive directors \| Award Date, 2018
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Shares vesting period						12 months
Shares expiration period						8 years
Employee Stock Option \| Minimum
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Options outstanding fair value (USD per share)	$ 12.24					$ 12.24
Employee Stock Option \| Maximum
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Weighted average contractual term of options outstanding	8 years
Options outstanding fair value (USD per share)	$ 64.07					$ 64.07
Restricted Stock Units 2013
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Ordinary shares which have been reserved for issuance (in shares)				4,100,000
Ordinary shares which have been reserved for issuance (in shares)				2,500,000
Consultants Restricted Stock Units 2019
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Ordinary shares which have been reserved for issuance (in shares)									250,000
Consultants Restricted Stock Units 2019 \| Non-executive directors
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Shares vesting period						12 months
Performance Share Unit (PSUs)
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Fair value of stock units vested						$ 5,100,000		$ 5,300,000
Restricted Stock Units (RSUs)
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Fair value of stock units vested						$ 16,100,000		$ 14,300,000
PSUs Based on Service and EPS Targets \| Maximum
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Stock units to be granted (in shares)	83,897					83,897