Defined Contribution Plan Employee Immediately Vesting Percentage

No definition available.

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

- Definition

The maximum amount of compensation the entity can withhold annually for contribution into the ESPP.

+ References

No definition available.

+ Details

Name:	apei_EmployeeStockPurchasePlanMaximumAmountOfAnnualCompensationToPurchaseSharesByEligibleParticipants
Namespace Prefix:	apei_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The maximum fair value, as defined, of shares that a participant can purchase each year under the ESPP.

+ References

No definition available.

+ Details

Name:	apei_EmployeeStockPurchasePlanMaximumAnnualFairValueOfSharesPurchasedByParticipant
Namespace Prefix:	apei_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Employee Stock Purchase Plan, Termination Period

+ References

No definition available.

+ Details

Name:	apei_EmployeeStockPurchasePlanTerminationPeriod
Namespace Prefix:	apei_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

+ References

No definition available.

+ Details

Name:	us-gaap_DefinedContributionPlanEmployerDiscretionaryContributionAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

+ References

No definition available.

+ Details

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

- Definition

Number of additional shares authorized for issuance under share-based payment arrangement.

+ References

No definition available.

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfAdditionalSharesAuthorized
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of shares authorized for issuance under share-based payment arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

+ Details

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

- Definition

Purchase price of common stock expressed as a percentage of its fair value.

+ References

No definition available.

+ Details

Name:	us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardPurchasePriceOfCommonStockPercent
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_PlanNameAxis=apei_AmericanPublicEducationIncEmployeeStockPurchasePlanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Other Employee Benefits - Narrative (Details) - USD ($)			12 Months Ended
Other Employee Benefits - Narrative (Details) - USD ($)	May 15, 2020	Jun. 13, 2014	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of gross annual earnings (up to)			60.00%
Percentage vested in salary reduction contributions			100.00%
Discretionary contributions			$ 4,200,000	$ 3,700,000	$ 3,700,000
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payroll deduction period (up to)			5 days
Percentage of fair market value			85.00%
Threshold amount of total amount of contributions			$ 21,000
Threshold amount of common stock			$ 25,000
Shares of common stock available (in shares)			100,000
Common stock available for issuance (in shares)	100,000	100,000