Acquisitions (Acquired Intangible Assets Subject to Amortization and Values and Estimated Useful Lives) (Details) $ in Thousands	Aug. 12, 2021 USD ($)
Walden University, LLC [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Intangible assets, finite lived	$ 161,900
Amortizable intangible assets, estimated useful lives	3 years
Walden University, LLC [Member] | Curriculum/software [Member]
Business Acquisition [Line Items]
Intangible assets, finite lived	$ 56,091
Amortizable intangible assets, estimated useful lives	5 years
OnCourse Learning [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Amortizable intangible assets, estimated useful lives	3 years
OnCourse Learning [Member] | Curriculum/software [Member]
Business Acquisition [Line Items]
Amortizable intangible assets, estimated useful lives	5 years