Cash purchase price for each equity award held, including stock options and restricted stock units (RSUs).

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Per share amount paid for the shares of the subsidiary purchased by the parent during the period, thereby effecting a change in total (consolidated) equity attributable to the parent.

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No definition available.

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Number of shares of the subsidiary purchased by the parent during the period, thereby effecting a change in total (consolidated) equity attributable to the parent.

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The aggregate amount paid by the entity to cancel subsidiary's outstanding equity awards.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan, net of adjustments to a previously accrued restructuring liability. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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No definition available.

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Amount of direct costs of the business combination including legal, accounting, and other costs incurred to consummate the business acquisition.

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No definition available.

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Represents the purchase by the parent of an additional equity interest in a subsidiary during the period, thereby effecting a change in total (consolidated) equity attributable to the parent. The purchase of the additional equity interest represented by this element increases the parent's controlling interest in the subsidiary.

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

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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No definition available.

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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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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.

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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.

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Amount of expense (reversal of expense) which increases (decreases) the restructuring reserve from an adjustment to a previously accrued restructuring liability.

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Akcea Merger (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	1 Months Ended	3 Months Ended	12 Months Ended		24 Months Ended
	Oct. 31, 2020	Dec. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2021	Sep. 30, 2020
Akcea Merger [Member]
Severance and Retention Costs [Abstract]
Beginning balance			$ 14.7
Amount expensed during the year			13.5
Reserve adjustments during the year			(1.8)
Net amount expensed during the year			11.7	$ 15.3	$ 27.0
Amounts paid during the year			(26.4)
Ending balance		$ 14.7		14.7
Akcea Merger [Member] \| Accrued Compensation [Member]
Severance and Retention Costs [Abstract]
Ending balance			0.0		$ 0.0
Akcea Merger [Member] \| R&D Expenses [Member]
Severance and Retention Costs [Abstract]
Net amount expensed during the year			5.1	3.9
Akcea Merger [Member] \| SG&A Expenses [Member]
Severance and Retention Costs [Abstract]
Net amount expensed during the year			$ 6.6	11.4
Akcea [Member]
Akcea Merger [Abstract]
Percentage ownership	100.00%		100.00%		100.00%	76.00%
Shares purchased (in shares)	24.8
Purchase price per share (in dollars per share)	$ 18.15
Purchase price	$ 450.6
Direct transaction costs		$ 40.6		$ 40.6
Cash purchase price of equity awards (in dollars per share)		$ 18.15
Payments for cancelled equity awards		$ 53.4
Unrecognized compensation cost related to non-vested units	$ 59.3