Significant Accounting Policies, Noncontrolling Interest in Akcea (Details)	Sep. 30, 2020	Jun. 30, 2017
Akcea [Member]
Noncontrolling Interest in Akcea Therapeutics, Inc. [Abstract]
Percentage ownership	76.00%	100.00%

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

No definition available.

Name:	us-gaap_MinorityInterestOwnershipPercentageByParent
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant