Debt Instrument, Grace Period

No definition available.

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Namespace Prefix:	crto_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Line of Credit Facility, Maximum Borrowing Capacity, Amount Of Decrease Each Subsequent Year

+ References

No definition available.

+ Details

Name:	crto_LineofCreditFacilityMaximumBorrowingCapacityAmountOfDecreaseEachSubsequentYear
Namespace Prefix:	crto_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ Details

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Namespace Prefix:	us-gaap_
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

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

Name:	us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_LineOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=crto_BankSyndicateRCFMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=crto_BpifranceFinancementFrenchPublicInvestmentBankRCFMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=crto_Euribor3MonthsMember
Namespace Prefix:
Data Type:	na
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- Details

Name:	us-gaap_DebtInstrumentAxis=crto_CentralRCFMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=crto_HSBCRevolvingLoanFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=crto_PeoplesBankofChinaRateEffectiveonLoanDrawdownDateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_LoansPayableMember
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- Details

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Financial Liabilities - Additional Information (Details)	1 Months Ended			12 Months Ended
	Sep. 30, 2015 EUR (€)	May 31, 2015 CNY (¥)	Feb. 28, 2014 EUR (€)	Dec. 31, 2016 CNY (¥)	Dec. 31, 2016 EUR (€)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 CNY (¥)	Dec. 31, 2015 EUR (€)	Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)	May 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Oct. 31, 2014 CNY (¥)	Feb. 28, 2014 USD ($)
Debt Instrument [Line Items]
Amount drawn \| $						$ 82,921,000			$ 9,245,000			$ 13,051,000
Line of Credit \| Bank Syndicate RCF \| Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity	€ 250,000,000				€ 250,000,000.0	263,500,000.0				$ 263,500,000.0
Amount drawn					75,000,000	75,000,000
Line of Credit \| Bpifrance Financement (French Public Investment Bank) RCF \| Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity					2,000,000
Amount drawn					50,000	100,000
Line of Credit \| Bpifrance Financement (French Public Investment Bank) RCF \| Revolving Credit Facility \| Euribor 3 Months
Debt Instrument [Line Items]
Basis spread on variable rate				0.70%
Line of Credit \| Central RCF \| Revolving Credit Facility
Debt Instrument [Line Items]
Amount drawn					100,000
Line of Credit \| HSBC Revolving Loan Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity		¥ 40,000,000.0		¥ 40,000,000.0		5,800,000.0					$ 5,800,000.0		¥ 15,000,000
Amount drawn				¥ 30,000,000		$ 4,300,000	¥ 25,000,000		3,900,000
Line of Credit \| HSBC Revolving Loan Facility \| Revolving Credit Facility \| People’s Bank of China Rate Effective on Loan Drawdown Date
Debt Instrument [Line Items]
Basis spread on variable rate				10.00%
Revolving Credit Facility \| Bank Syndicate RCF
Debt Instrument [Line Items]
Debt instrument, term (in years)	5 years
Revolving Credit Facility \| Bpifrance Financement (French Public Investment Bank) RCF
Debt Instrument [Line Items]
Debt instrument, term (in years)			3 years
Maximum borrowing capacity			€ 3,000,000.0					€ 1,000,000.0	$ 1,000,000.0					$ 3,200,000.0
Amount of decrease each subsequent year			€ 1,000,000											1,000,000
Commitment fee percentage			0.30%
Revolving Credit Facility \| Bpifrance Financement (French Public Investment Bank) RCF \| Euribor 3 Months
Debt Instrument [Line Items]
Basis spread on variable rate			0.70%
Revolving Credit Facility \| HSBC Revolving Loan Facility \| People’s Bank of China Rate Effective on Loan Drawdown Date
Debt Instrument [Line Items]
Basis spread on variable rate		10.00%
Loans Payable \| 2.09% Bpifrance Financement (Fench Public Investment Bank) Term Loan
Debt Instrument [Line Items]
Debt instrument, term (in years)			7 years
Debt instrument, face amount			€ 3,000,000		€ 3,000,000									$ 3,200,000.0
Grace period (in years)			2 years