Number of separate performance periods under share-based payment arrangement.

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- Definition

Number of units guaranteed to vest under share-based payment arrangement.

+ References

No definition available.

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- Definition

Percentage of units guaranteed to vest under share-based payment arrangement.

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No definition available.

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- Definition

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 718
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- References

No definition available.

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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

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

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- Definition

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

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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.

+ References

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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No definition available.

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

+ References

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

Rate of weighted-average expected volatility for award under share-based payment arrangement.

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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

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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Percentage of vesting of award under share-based payment arrangement.

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- Definition

Expected term of 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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Significant Accounting Policies, Stock-Based Compensation Expense (Details) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2021 USD ($) Period $ / shares shares	Jun. 30, 2020 USD ($) shares
Stock-based Compensation Expense [Abstract]
Non-cash stock-based compensation expense	$ 30,022	$ 48,442	$ 67,882	$ 89,233
Cost of Sales [Member]
Stock-based Compensation Expense [Abstract]
Non-cash stock-based compensation expense	0	350	182	587
Research, Development and Patent Expense [Member]
Stock-based Compensation Expense [Abstract]
Non-cash stock-based compensation expense	22,748	26,016	48,647	51,573
Selling, General and Administrative Expense [Member]
Stock-based Compensation Expense [Abstract]
Non-cash stock-based compensation expense	7,274	$ 22,076	19,053	$ 37,073
Stock Options [Member]
Unrecognized Compensation Expense [Abstract]
Unrecognized compensation expense related to non-vested stock options	79,000		$ 79,000
Weighted average period for recognition			1 year 3 months 18 days
Stock Options [Member] \| Board of Directors [Member]
Stock-based Compensation Expense [Abstract]
Stock options granted (in shares) \| shares			0	0
Stock Options [Member] \| Employees [Member]
Weighted-Average Assumptions [Abstract]
Risk-free interest rate			0.50%	1.60%
Dividend yield			0.00%	0.00%
Volatility			54.80%	58.90%
Expected life			4 years 10 months 24 days	4 years 8 months 12 days
ESPP [Member]
Weighted-Average Assumptions [Abstract]
Risk-free interest rate			0.10%	1.10%
Dividend yield			0.00%	0.00%
Volatility			39.10%	47.20%
Expected life			6 months	6 months
RSUs [Member]
Unrecognized Compensation Expense [Abstract]
Unrecognized compensation cost related to non-vested units	86,300		$ 86,300
Weighted average period for recognition			1 year 7 months 6 days
RSUs [Member] \| Board of Directors [Member]
Stock-based Compensation Expense [Abstract]
Units granted (in shares) \| shares			0	0
RSUs [Member] \| Board of Directors [Member] \| Maximum [Member]
RSUs and PRSUs [Abstract]
Vesting period			4 years
RSUs [Member] \| Board of Directors [Member] \| Minimum [Member]
RSUs and PRSUs [Abstract]
Vesting period			1 year
RSUs [Member] \| Employees [Member]
RSUs and PRSUs [Abstract]
Vesting period			4 years
Weighted-average grant date fair value (in dollars per share) \| $ / shares			$ 61.41
PRSUs [Member]
Unrecognized Compensation Expense [Abstract]
Unrecognized compensation cost related to non-vested units	$ 3,200		$ 3,200
Weighted average period for recognition			1 year 6 months
PRSUs [Member] \| Chief Executive Officer, Dr. Brett Monia [Member]
RSUs and PRSUs [Abstract]
Number of performance periods \| Period			3
Vesting period			3 years
Number of units guaranteed to vest \| shares			0
Weighted-average grant date fair value (in dollars per share) \| $ / shares			$ 77.17
PRSUs [Member] \| Chief Executive Officer, Dr. Brett Monia [Member] \| Maximum [Member]
RSUs and PRSUs [Abstract]
Percentage of units guaranteed to vest			150.00%
PRSUs [Member] \| Chief Executive Officer, Dr. Brett Monia [Member] \| Minimum [Member]
RSUs and PRSUs [Abstract]
Percentage of units guaranteed to vest			0.00%
PRSUs [Member] \| Chief Executive Officer, Dr. Brett Monia [Member] \| One-Year Period [Member]
RSUs and PRSUs [Abstract]
Vesting percentage			33.30%
PRSUs [Member] \| Chief Executive Officer, Dr. Brett Monia [Member] \| Two-Year Period [Member]
RSUs and PRSUs [Abstract]
Vesting percentage			33.30%
PRSUs [Member] \| Chief Executive Officer, Dr. Brett Monia [Member] \| Three-Year Period [Member]
RSUs and PRSUs [Abstract]
Vesting percentage			33.30%