Significant Events and Transactions of the Period - Summary of Restructuring Reserve (Details) $ in Thousands	3 Months Ended
Mar. 31, 2020 USD ($)
Closing R&D Operations In Palo Alto
Restructuring Reserve [Roll Forward]
Beginning balance	$ 5,581
Restructuring costs	449
Amounts paid	(3,788)
Ending balance	2,242
New Organization Structure
Restructuring Reserve [Roll Forward]
Beginning balance	510
Restructuring costs	772
Amounts paid	(686)
Ending balance	$ 596

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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- Definition

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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