Revenue Recognition - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	2 Months Ended	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Disaggregation of revenue
Revenues		$ 160,945	$ 108,512	$ 392,082	$ 336,144
Strayer
Disaggregation of revenue
Revenues		114,471	107,321	343,644	332,094
Strayer | Tuition, net of discounts, grants and scholarships
Disaggregation of revenue
Revenues		107,804	103,453	328,613	320,658
Strayer | Other Revenue
Disaggregation of revenue
Revenues		6,667	3,868	15,031	11,436
Capella
Disaggregation of revenue
Revenues		43,792		43,792
Subscription period for FlexPath courses	84 days
Capella | Tuition, net of discounts, grants and scholarships
Disaggregation of revenue
Revenues		40,749		40,749
Capella | Other Revenue
Disaggregation of revenue
Revenues		3,043		3,043
Non-Degree Programs
Disaggregation of revenue
Revenues		$ 2,682	$ 1,191	$ 4,646	$ 4,050