The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(ii)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 718
-SubTopic 10
-Subparagraph (e)(1)
-Name Accounting Standards Codification
-Paragraph 2
-Section 50
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

+ Details

Name:	us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis=prdo_RangeOfExercisePricesOneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis=prdo_RangeOfExercisePricesTwoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis=prdo_RangeOfExercisePricesThreeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis=prdo_RangeOfExercisePricesFourMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis=prdo_RangeOfExercisePricesFiveMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis=prdo_RangeOfExercisePricesSixMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis=prdo_RangeOfExercisePricesSevenMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis=prdo_RangeOfExercisePricesEightMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Share-Based Compensation - Schedule of Information with Respect to Outstanding and Exercisable Stock Options (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding, Number of Options Outstanding	383,216	541,263	851,082	995,091
Options Outstanding, Weighted Average Exercise Price	$ 9.90	$ 10.65	$ 9.45	$ 9.02
Options Outstanding, Weighted Average Remaining Contractual Term (in Years)	2 years 2 months 1 day
Options Exercisable, Number Exercisable	383,216
Options Exercisable, Weighted Average Exercise Price	$ 9.90
Range of Exercise Prices $3.93 - $3.93 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding, Number of Options Outstanding	79,992
Options Outstanding, Weighted Average Exercise Price	$ 3.93
Options Outstanding, Weighted Average Remaining Contractual Term (in Years)	4 months 17 days
Options Exercisable, Number Exercisable	79,992
Options Exercisable, Weighted Average Exercise Price	$ 3.93
Range of Exercise Prices $5.96 - $5.96 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding, Number of Options Outstanding	84,516
Options Outstanding, Weighted Average Exercise Price	$ 5.96
Options Outstanding, Weighted Average Remaining Contractual Term (in Years)	1 year 4 months 20 days
Options Exercisable, Number Exercisable	84,516
Options Exercisable, Weighted Average Exercise Price	$ 5.96
Range of Exercise Prices $7.22 - $7.22 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding, Number of Options Outstanding	9,308
Options Outstanding, Weighted Average Exercise Price	$ 7.22
Options Outstanding, Weighted Average Remaining Contractual Term (in Years)	1 year 10 months 6 days
Options Exercisable, Number Exercisable	9,308
Options Exercisable, Weighted Average Exercise Price	$ 7.22
Range of Exercise Prices $8.30 - $8.30 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding, Number of Options Outstanding	14,932
Options Outstanding, Weighted Average Exercise Price	$ 8.3
Options Outstanding, Weighted Average Remaining Contractual Term (in Years)	2 years 2 months 4 days
Options Exercisable, Number Exercisable	14,932
Options Exercisable, Weighted Average Exercise Price	$ 8.3
Range of Exercise Prices $9.69 - $9.69 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding, Number of Options Outstanding	56,355
Options Outstanding, Weighted Average Exercise Price	$ 9.69
Options Outstanding, Weighted Average Remaining Contractual Term (in Years)	2 years 4 months 20 days
Options Exercisable, Number Exercisable	56,355
Options Exercisable, Weighted Average Exercise Price	$ 9.69
Range of Exercise Prices $13.80 - $13.80 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding, Number of Options Outstanding	62,064
Options Outstanding, Weighted Average Exercise Price	$ 13.8
Options Outstanding, Weighted Average Remaining Contractual Term (in Years)	3 years 2 months 4 days
Options Exercisable, Number Exercisable	62,064
Options Exercisable, Weighted Average Exercise Price	$ 13.8
Range of Exercise Prices $15.39 - $15.39 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding, Number of Options Outstanding	40,085
Options Outstanding, Weighted Average Exercise Price	$ 15.39
Options Outstanding, Weighted Average Remaining Contractual Term (in Years)	3 years 4 months 28 days
Options Exercisable, Number Exercisable	40,085
Options Exercisable, Weighted Average Exercise Price	$ 15.39
Range of Exercise Prices $21.29 - $21.29 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding, Number of Options Outstanding	35,964
Options Outstanding, Weighted Average Exercise Price	$ 21.29
Options Outstanding, Weighted Average Remaining Contractual Term (in Years)	4 years 7 months 9 days
Options Exercisable, Number Exercisable	35,964
Options Exercisable, Weighted Average Exercise Price	$ 21.29