Debt Instrument, Convertible, Discount For Conversion Option

No definition available.

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Namespace Prefix:	chgg_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Debt Instrument, Convertible, Issuance Costs

+ References

No definition available.

+ Details

Name:	chgg_DebtInstrumentConvertibleIssuanceCosts
Namespace Prefix:	chgg_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=120520924&loc=SL6031897-161870

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28551-108399

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-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, after accumulated amortization, of debt discount (premium).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

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Period Type:	instant

- Details

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- Details

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Namespace Prefix:
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- Details

Name:	us-gaap_DebtInstrumentAxis=chgg_A0.125PercentConvertibleSeniorNotesDue2025Member
Namespace Prefix:
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Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=chgg_A0.25PercentConvertibleSeniorNotesDue2023Member
Namespace Prefix:
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Balance Type:
Period Type:

- Details

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Convertible Senior Notes - Net Carrying Amount (Details) - Shares related to convertible senior notes - USD ($)	Dec. 31, 2020	Aug. 31, 2020	Dec. 31, 2019	Apr. 30, 2019	Mar. 31, 2019	Apr. 30, 2018
0% Convertible Senior Notes Due 2026
Debt Instrument [Line Items]
Principal amount	$ 1,000,000,000	$ 1,000,000,000.0
Unamortized debt discount	(226,732,000)
Unamortized issuance costs	(11,338,000)	(15,900,000)
Debt discount for conversion option	241,300,000
Issuance costs	(3,838,000)
Net carrying amount (equity)	237,462,000	$ 241,300,000
0.125 Percent Convertible Senior Notes Due 2025
Debt Instrument [Line Items]
Principal amount	800,000,000		$ 800,000,000		$ 700,000,000
Unamortized debt discount	(149,138,000)		(184,698,000)
Unamortized issuance costs	(10,248,000)		(12,691,000)	$ (19,800,000)
Debt discount for conversion option	212,000,000		212,000,000
Issuance costs	(5,253,000)		(5,253,000)
Net carrying amount (equity)	206,747,000		206,747,000	$ 212,000,000.0
0.25% Convertible Senior Notes Due 2023
Debt Instrument [Line Items]
Principal amount	115,576,000		345,000,000			$ 345,000,000
Unamortized debt discount	(9,953,000)		(42,280,000)
Unamortized issuance costs	(1,245,000)		(5,028,000)			(9,400,000)
Debt discount for conversion option	21,505,000		64,193,000
Issuance costs	(586,000)		(1,749,000)
Net carrying amount (equity)	20,919,000		62,444,000			$ 64,200,000
Carrying Amount \| Fair Value, Nonrecurring
Debt Instrument [Line Items]
Net carrying amount (liability)	1,506,922,000		900,303,000
Carrying Amount \| Fair Value, Nonrecurring \| 0% Convertible Senior Notes Due 2026
Debt Instrument [Line Items]
Net carrying amount (liability)	761,930,000		0
Carrying Amount \| Fair Value, Nonrecurring \| 0.125 Percent Convertible Senior Notes Due 2025
Debt Instrument [Line Items]
Net carrying amount (liability)	640,614,000		602,611,000
Carrying Amount \| Fair Value, Nonrecurring \| 0.25% Convertible Senior Notes Due 2023
Debt Instrument [Line Items]
Net carrying amount (liability)	$ 104,378,000		$ 297,692,000