Liability Related to the Revenue Interest Purchase Agreement - Summary of Interest Liability (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Liability From Sale Of Future Revenues [Roll Forward]
Oberland funding for regulatory approval of NEXLETOL	$ 25,000
Revenue Interest Purchase Agreement (RIPA)
Liability From Sale Of Future Revenues [Roll Forward]
Revenue interest liability at December 31, 2019	132,544
Interest expense recognized	19,560	$ 8,100
Revenue interest payments	(500)
Revenue interest liability at December 31, 2020	$ 176,604	$ 132,544

The expense charged against earnings for the periodic recognition of the advance royalties. These royalties are paid in one accounting period, but are deducted from earnings over time through amortization. For example, royalties that are required to be paid in advance of production from a mineral, oil, or gas property and amortized over the period of right to produce these items.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.3)
-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration