Segment Reporting - Additional Information (Detail)	9 Months Ended
Sep. 30, 2020 Segment
Segment Reporting Information [Line Items]
Number of reporting segments	2
CTU [Member]
Segment Reporting Information [Line Items]
Students enrolled expressed as percentage of enrollment	56.00%
CTU [Member] \| Fully Online [Member]
Segment Reporting Information [Line Items]
Percentage of enrollment	95.00%
AIU [Member]
Segment Reporting Information [Line Items]
Students enrolled expressed as percentage of enrollment	44.00%
Acquisition date	Mar. 02, 2020
AIU [Member] \| Fully Online [Member]
Segment Reporting Information [Line Items]
Percentage of enrollment	97.00%

Percentage of enrollment.

No definition available.

Name:	prdo_PercentageOfEnrollment
Namespace Prefix:	prdo_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The percentage of student enrollment for a specific group of the total entity.

+ References

No definition available.

+ Details

Name:	prdo_PercentageOfStudentEnrollment
Namespace Prefix:	prdo_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Date when the acquirer obtains control of the acquiree, in CCYY-MM-DD format.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=116868678&loc=d3e848-128460

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=116868678&loc=d3e845-128460

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

+ Details

Name:	us-gaap_BusinessAcquisitionEffectiveDateOfAcquisition1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8672-108599

+ Details

Name:	us-gaap_NumberOfReportableSegments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

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

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=prdo_CTUMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ProductOrServiceAxis=prdo_FullyOnlineProgramMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=prdo_AIUMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: