Cyclerion Separation - Summary of Assets and Liabilities Held for Disposition (Details) - Discontinued Operations, Disposed of by Means Other than Sale, Spinoff - sGC Business - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Assets:
Assets	$ 0	$ 0
Liabilities:
Liabilities	$ 0	$ 0

Amount classified as liabilities attributable to disposal group held for sale or disposed of.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant