Consolidated Income Statements (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Income Statement [Abstract]
Net revenue	$ 236,818	$ 218,301	$ 512,499	$ 466,507
Costs and expenses:
Instructional costs and services	102,237	95,030	213,264	197,604
Admissions advisory and related	34,254	31,085	69,108	63,057
Advertising	27,602	24,776	53,317	49,407
Marketing and promotional	2,268	2,264	4,952	4,724
General and administrative	11,969	10,058	23,278	19,999
Total costs and expenses	178,330	163,213	363,919	334,791
Operating income	58,488	55,088	148,580	131,716
Interest expense	(57)	(495)	(403)	(1,075)
Interest and other income	1,567	739	2,548	741
Income before income taxes	59,998	55,332	150,725	131,382
Income tax expense	13,960	15,485	31,006	35,623
Net income	$ 46,038	$ 39,847	$ 119,719	$ 95,759
Earnings per share:
Basic income per share	$ 0.97	$ 0.85	$ 2.52	$ 2.04
Diluted income per share	$ 0.95	$ 0.83	$ 2.47	$ 1.99
Basic weighted average shares outstanding	47,604	47,151	47,537	46,949
Diluted weighted average shares outstanding	48,411	48,192	48,422	48,131

Admissions advisory and related expenses.

No definition available.

Name:	lope_AdmissionsAdvisoryAndRelatedExpenses
Namespace Prefix:	lope_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Costs directly attributable to educational services, including salaries and benefits for full-time faculty, administrators and academic advisors, and costs associated with adjunct faculty. Also includes costs for educational supplies such as books, costs associated with academic records and graduation, costs associated with collections from our students such as bad debt expense, and other university services such as evaluating transcripts.

+ References

No definition available.