Financial Instruments - Additional Information (Detail) - USD ($)	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Financial Instruments [Line Items]
Period cash equivalents and short-term investments have been in continuous unrealized gain (loss) position, years, maximum	1 year
Realized gains (losses)	$ 0	$ 0

The maximum length of time, in years, that the amount of investment in debt and equity securities categorized neither as trading securities nor held-to-maturity securities and intended be sold or mature one year or operating cycle, if longer, are in a continuous unrealized loss/gain position.

No definition available.

Name:	prdo_ShortTermInvestmentContinuousUnrealizedGainLossPositionPeriod
Namespace Prefix:	prdo_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration