Reduction in revenue due to scholarships offered to students.

No definition available.

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Balance Type:	debit
Period Type:	duration

- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer before revenue reduction adjustments.

+ References

No definition available.

+ Details

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- 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

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- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

+ Details

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Data Type:	xbrli:monetaryItemType
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- Details

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

- Details

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Summary of Significant Accounting Policies - Summary of Revenues Disaggregated by Nature of Transfer of Services (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Jun. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Disaggregation of Revenue [Line Items]
Total revenues			$ 613,675
Scholarships			(101,176)
Net Revenues	$ 193,289	$ 155,454	512,499	$ 565,396	$ 667,953
Tuition Revenues [Member]
Disaggregation of Revenue [Line Items]
Total revenues			522,430
Ancillary Revenues [Member]
Disaggregation of Revenue [Line Items]
Total revenues			$ 91,245