Cover Page - USD ($) $ in Billions	12 Months Ended
	Dec. 31, 2021	Jan. 28, 2022	Jun. 30, 2021
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2021
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity File Number	0-21039
Entity Registrant Name	STRATEGIC EDUCATION, INC.
Entity Incorporation, State or Country Code	MD
Entity Tax Identification Number	52-1975978
Entity Address, Address Line One	2303 Dulles Station Boulevard
Entity Address, City or Town	Herndon,
Entity Address, State or Province	VA
Entity Address, Postal Zip Code	20171
City Area Code	703
Local Phone Number	561-1600
Title of 12(b) Security	COMMON STOCK, $0.01 PAR VALUE
Trading Symbol	STRA
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Public Float			$ 1.8
Entity Common Stock, Shares Outstanding (in shares)		24,592,098
Documents Incorporated by Reference	Certain portions of the registrant’s Definitive Proxy Statement for its 2022 Annual Meeting of Stockholders (which is expected to be filed with the Commission within 120 days after the end of the registrant’s 2021 fiscal year) are incorporated by reference into Part III of this Annual Report.
Entity Central Index Key	0001013934
Amendment Flag	false
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2021