Cover Page - shares	6 Months Ended
	Jun. 30, 2020	Jul. 31, 2020
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2020
Document Transition Report	false
Entity File Number	001-36180
Entity Registrant Name	CHEGG, INC
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	20-3237489
Entity Address, Address Line One	3990 Freedom Circle
Entity Address, City or Town	Santa Clara
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	95054
City Area Code	408
Local Phone Number	855-5700
Title of 12(b) Security	Common stock, $0.001 par value per share
Trading Symbol	CHGG
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		124,314,241
Entity Central Index Key	0001364954
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q2
Amendment Flag	false