Subsequent Events	3 Months Ended
	Mar. 31, 2022
Subsequent Events [Abstract]
Subsequent Events	Subsequent EventsIn May 2022, the Company entered into a term loan facility (the “Oxford Loan Agreement”) with Oxford Finance LLC for up to $100.0 million. Pursuant to the Agreement, the Company received an initial term loan of $10.0 million of an initial $25.0 million tranche at closing, with the remaining $15.0 million available through the end of the year. The Company has access to an additional $75.0 million over three tranches, $50.0 million of which is at its option upon the satisfaction of certain conditions related to the development of PLN-74809 and one of the Company’s preclinical product candidates, and $25.0 million at the Lender’s discretion. Borrowings under the Oxford Loan Agreement bear interest at a rate per annum equal to 1-month term Secured Overnight Financing Rate (SOFR) plus 8.5%, subject to an agreed upon floor and cap. The Oxford Loan Agreement requires the Company to make monthly interest-only payments until July 1, 2026 (extendable to July 1, 2027) with monthly interest and principal payments thereafter until the maturity date of May 1, 2027 (extendable to May 1, 2028). There are no warrants or financial covenants in the Oxford Loan Agreement.