Revenue - American Public University System Tuition Refund Schedule (Details) - American Public Education Segment	12 Months Ended
Dec. 31, 2019
Eight Week Course
Disaggregation of Revenue [Line Items]
Before or During Week 1	100.00%
During Week 2	75.00%
During Weeks 3 through 4	50.00%
During Weeks 5 through 8	0.00%
Sixteen Week Course
Disaggregation of Revenue [Line Items]
Before or During Week 1	100.00%
During Week 2	100.00%
During Weeks 3 through 4	75.00%
During Weeks 5 through 8	50.00%
During Weeks 9 through 16	0.00%

- Definition

The refund percentage applied to tuition fees to which a student is entitled if he or she drops out before or during the first week of class.

+ References

No definition available.

+ Details

Name:	apei_TuitionRefundPercentageBeforeOrDuringWeekOne
Namespace Prefix:	apei_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The refund percentage applied to tuition fees to which a student is entitled if he or she drops out during the second week of class.

+ References

No definition available.

+ Details

Name:	apei_TuitionRefundPercentageDuringWeekTwo
Namespace Prefix:	apei_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The refund percentage applied to tuition fees to which a student is entitled if he or she drops out during the fifth through eighth week of class.

+ References

No definition available.

+ Details

Name:	apei_TuitionRefundPercentageDuringWeeksFiveThroughEight
Namespace Prefix:	apei_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The refund percentage applied to tuition fees to which a student is entitled if he or she drops out during the ninth through sixteenth week of class.

+ References

No definition available.

+ Details

Name:	apei_TuitionRefundPercentageDuringWeeksNineThroughSixteen
Namespace Prefix:	apei_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The refund percentage applied to tuition fees to which a student is entitled if he or she drops out during the third or fourth week of class.

+ References

No definition available.

+ Details

Name:	apei_TuitionRefundPercentageDuringWeeksThreeThroughFour
Namespace Prefix:	apei_
Data Type:	num:percentItemType
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_DisaggregationOfRevenueLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

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

- Details

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

- Details

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