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This element represents the money received from shareholders on notes receivable.

No definition available.

Name:	crai_PaymentsReceivedOnNotesReceivableFromShareholders
Namespace Prefix:	crai_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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The amount of adjustment to stockholders' equity associated with an employee's income tax withholding obligation as part of a net-share settlement of a share-based award.

No definition available.

Name:	us-gaap_AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation
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Amount of decrease in additional paid in capital (APIC) resulting from a tax deficiency associated with a share-based compensation plan other than an employee stock ownership plan (ESOP).

No definition available.

Name:	us-gaap_AdjustmentsToAdditionalPaidInCapitalIncomeTaxDeficiencyFromShareBasedCompensation
Namespace Prefix:	us-gaap_
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This element represents the amount of recognized equity-based compensation during the period, that is, the amount recognized as expense in the income statement (or as asset if compensation is capitalized). Alternate captions include the words "stock-based compensation".

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Amount of increase in noncontrolling interest from sale of a portion of the parent's controlling interest.

No definition available.

Name:	us-gaap_NoncontrollingInterestIncreaseFromSaleOfParentEquityInterest
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Name:	us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax
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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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Name:	us-gaap_ProfitLoss
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For net-share settlement of share-based awards when the employer settles employees' income tax withholding obligations, this element represents the number of shares the employees use to repay the employer.

No definition available.

Name:	us-gaap_SharesPaidForTaxWithholdingForShareBasedCompensation
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

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Name:	us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest
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Number of shares of stock issued during the period pursuant to acquisitions.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

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Period Type:	duration

Number of share options (or share units) exercised during the current period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Name:	us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised
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Period Type:	duration

Value of stock issued pursuant to acquisitions during the period.

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Name:	us-gaap_StockIssuedDuringPeriodValueAcquisitions
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Value of stock issued as a result of the exercise of stock options.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

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-Number 210

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Number of shares that have been repurchased and retired during the period.

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Namespace Prefix:	us-gaap_
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Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).