Subsequent Event	12 Months Ended
Dec. 31, 2020
Subsequent Events [Abstract]
Subsequent Event	Subsequent EventOn February 17, 2021, we entered into an underwriting agreement pursuant to which we agreed to issue and sell 9,804,000 shares of our common stock at a public offering price of $102.00 per share and on February 18, 2021, the option to purchase up to an additional 1,470,600 shares of our common stock, consisting of 300,000 shares of common stock from the selling stockholder and 1,170,600 shares issued by us, was exercised (the “Offering”). On February 22, 2021, we closed the Offering and issued the shares for estimated net proceeds of approximately $1,091.6 million, after deducting underwriting discounts and commissions and estimated Offering expenses payable by Chegg.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

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