Segments - Adjusted EBITDA by Reportable Segment (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Segment Reporting Information [Line Items]
Segment Adjusted EBITDA for reportable segments	$ (13,596)	$ (7,358)	$ (12,862)	$ (16,178)
Biopharmaceuticals
Segment Reporting Information [Line Items]
Segment Adjusted EBITDA for reportable segments	(12,661)	(8,761)	(34,055)	(26,106)
Exemplar
Segment Reporting Information [Line Items]
Segment Adjusted EBITDA for reportable segments	1,617	1,654	5,312	2,511
Trans Ova
Segment Reporting Information [Line Items]
Segment Adjusted EBITDA for reportable segments	$ (2,552)	$ (251)	$ 15,881	$ 7,417

Segment Adjusted EBITDA defined as net income (loss) before (i) interest expense, (ii) income tax expense/benefit, (iii) depreciation and amortization, (iv) stock-based compensation expense, (v) loss on settlement agreements where noncash consideration is paid; (vi) adjustments for accrued bonuses paid in equity awards; (vii) gain or loss on disposal of assets; (viii) loss on impairment of goodwill and other noncurrent assets, (ix) write-off of reacquired in-process research and development, (x) equity in net income (loss) of affiliates, and (xi) recognition of previously deferred revenue associated with upfront and milestone payments as well as cash outflows from capital expenditures and investments in affiliates, but includes proceeds from the sale of assets in the period sold.

No definition available.

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Namespace Prefix:	pgen_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration