Number of Employees Performance-based Equity Awards Impacted by Change in Operational Milestones

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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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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Amount of cost to be recognized for option under share-based payment arrangement.

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Amount of additional cost recognized for award under share-based payment arrangement from occurrence of event accelerating recognition of cost.

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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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An excess of the fair value of the modified award over the fair value of the award immediately before the modification.

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- Definition

Number of shares for which recognition of cost was accelerated for award under share-based payment arrangement.

+ References

No definition available.

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STOCK-BASED COMPENSATION - Narrative (Details)	3 Months Ended		6 Months Ended
STOCK-BASED COMPENSATION - Narrative (Details)	Jun. 30, 2020 USD ($) employees shares	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($) employees shares	Jun. 30, 2019 USD ($)
Stock-based compensation
Stock-based compensation expense	$ 40,000,000.0	$ 20,100,000	$ 69,600,000	$ 36,300,000
Incremental share based compensation expense	$ 0		$ 0
Number of employees impacted by change in operational milestones \| employees	36		36
Non-cash stock-based compensation expense	$ 1,800,000
Stock Plans
Stock-based compensation
Unrecognized compensation cost	300,900,000		$ 300,900,000
Weighted average period for recognition of cost			3 years
Merger Agreement with Genomic Health, Inc.
Stock-based compensation
Non-cash stock-based compensation expense	$ 600,000		$ 3,500,000
Option Plan Shares
Stock-based compensation
Accelerated vesting, shares \| shares	708
Option Plan Shares \| Merger Agreement with Genomic Health, Inc.
Stock-based compensation
Accelerated vesting, shares \| shares	9,132		43,480
Restricted Shares and RSUs
Stock-based compensation
Accelerated vesting, shares \| shares	33,123
Restricted Shares and RSUs \| Merger Agreement with Genomic Health, Inc.
Stock-based compensation
Accelerated vesting, shares \| shares	10,525		28,814