CRA International (CRAI) 10-K 13 Mar 14 2013 FY Annual report Financial data

Document_and_Entity_Informatio

Document and Entity Information (USD $)	12 Months Ended
In Millions, except Share data, unless otherwise specified	Dec. 28, 2013	Mar. 06, 2014	Jun. 29, 2013
Document and Entity Information	'	'	'
Entity Registrant Name	'CRA INTERNATIONAL, INC.	'	'
Entity Central Index Key	'0001053706	'	'
Document Type	'10-K	'	'
Document Period End Date	28-Dec-13	'	'
Amendment Flag	'false	'	'
Current Fiscal Year End Date	'--12-28	'	'
Entity Well-known Seasoned Issuer	'No	'	'
Entity Voluntary Filers	'No	'	'
Entity Current Reporting Status	'Yes	'	'
Entity Filer Category	'Accelerated Filer	'	'
Entity Public Float	'	'	$182
Entity Common Stock, Shares Outstanding	'	10,066,778	'
Document Fiscal Year Focus	'2013	'	'
Document Fiscal Period Focus	'FY	'	'

CONSOLIDATED_STATEMENTS_OF_OPE

CONSOLIDATED STATEMENTS OF OPERATIONS (USD $)	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 28, 2013	Dec. 29, 2012	Dec. 31, 2011
CONSOLIDATED STATEMENTS OF OPERATIONS	'	'	'
Revenues	$278,432	$270,390	$305,228
Costs of services	189,262	182,381	199,383
Gross profit	89,170	88,009	105,845
Selling, general and administrative expenses	64,242	67,235	71,752
Depreciation and amortization	6,411	7,190	5,029
Goodwill impairment	0	71,394	0
Income (loss) from operations	18,517	-57,810	29,064
Interest income	155	264	332
Interest expense	-574	-300	-908
Other expense, net	-180	-177	-405
Income (loss) before (provision) benefit for income taxes	17,918	-58,023	28,083
(Provision) benefit for income taxes	-6,683	5,180	-11,138
Net income (loss)	11,235	-52,843	16,945
Net (income) loss attributable to noncontrolling interest, net of tax	135	-147	-94
Net income (loss) attributable to CRA International, Inc.	$11,370	($52,990)	$16,851
Net income (loss) per share attributable to CRA International, Inc.:	'	'	'
Basic (in dollars per share)	$1.13	($5.21)	$1.60
Diluted (in dollars per share)	$1.12	($5.21)	$1.57
Weighted average number of shares outstanding:	'	'	'
Basic (in shares)	10,084	10,167	10,555
Diluted (in shares)	10,173	10,167	10,739

CONSOLIDATED_STATEMENTS_OF_COM

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 28, 2013	Dec. 29, 2012	Dec. 31, 2011
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS)	'	'	'
Net income (loss)	$11,235	($52,843)	$16,945
Other comprehensive income (loss):	'	'	'
Foreign currency translation adjustments	964	1,950	-676
Comprehensive income (loss)	12,199	-50,893	16,269
Less: comprehensive (income) loss attributable to noncontrolling interest	135	-147	-94
Comprehensive income (loss) attributable to CRA International, Inc.	$12,334	($51,040)	$16,175

CONSOLIDATED_BALANCE_SHEETS

CONSOLIDATED BALANCE SHEETS (USD $)	Dec. 28, 2013	Dec. 29, 2012
In Thousands, unless otherwise specified
Current assets:	'	'
Cash and cash equivalents	$51,251	$55,451
Accounts receivable, net of allowances of $7,210 at December 28, 2013 and $9,459 at December 29, 2012	57,856	56,083
Unbilled services	24,275	21,187
Prepaid expenses and other current assets	11,775	23,001
Deferred income taxes	17,806	15,955
Total current assets	162,963	171,677
Property and equipment, net	15,655	17,980
Goodwill	81,573	70,765
Intangible assets, net of accumulated amortization of $8,392 at December 28, 2013 and $7,122 at December 29, 2012	4,537	1,834
Deferred income taxes, net of current portion	955	8,083
Other assets	54,621	21,671
Total assets	320,304	292,010
Current liabilities:	'	'
Accounts payable	13,766	9,766
Accrued expenses	65,657	45,305
Deferred revenue and other liabilities	6,098	6,748
Deferred income taxes	0	1,145
Current portion of deferred rent	2,322	2,268
Current portion of notes payable	0	691
Current portion of deferred compensation	117	3,287
Total current liabilities	87,960	69,210
Notes payable, net of current portion	1,007	1,007
Deferred rent and facility-related non-current liabilities	3,669	5,608
Deferred compensation and other non-current liabilities	1,446	2,676
Deferred income taxes, net of current portion	1,585	1,275
Commitments and contingencies	'	'
Shareholders' equity:	'	'
Preferred stock, no par value; 1,000,000 shares authorized; none issued and outstanding	'	'
Common stock, no par value; 25,000,000 shares authorized; 10,048,611 and 10,057,448 shares issued and outstanding at December 28, 2013 and December 29, 2012, respectively	93,242	93,174
Receivables from shareholders	0	-120
Retained earnings	133,980	122,610
Accumulated other comprehensive loss	-3,424	-4,388
Total CRA International, Inc. shareholders' equity	223,798	211,276
Noncontrolling interest	839	958
Total shareholders' equity	224,637	212,234
Total liabilities and shareholders' equity	$320,304	$292,010

CONSOLIDATED_BALANCE_SHEETS_Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $)	Dec. 28, 2013	Dec. 29, 2012
In Thousands, except Share data, unless otherwise specified
CONSOLIDATED BALANCE SHEETS	'	'
Accounts receivable, allowances (in dollars)	$7,210	$9,459
Intangible assets, accumulated amortization (in dollars)	$8,392	$7,122
Preferred stock, par value (in dollars per share)	'	'
Preferred stock, shares authorized	1,000,000	1,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value ( in dollars per share )	'	'
Common stock, shares authorized	25,000,000	25,000,000
Common stock, shares issued	10,048,611	10,057,448
Common stock, shares outstanding	10,048,611	10,057,448

CONSOLIDATED_STATEMENTS_OF_CAS

CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 28, 2013	Dec. 29, 2012	Dec. 31, 2011
OPERATING ACTIVITIES:	'	'	'
Net income (loss)	$11,235	($52,843)	$16,945
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities, net of effect of acquired businesses:	'	'	'
Depreciation and amortization	6,460	5,841	5,103
Loss on disposal of property and equipment	16	1,444	146
Goodwill impairment	0	71,394	0
Deferred rent	-1,903	-4,475	-1,956
Deferred income taxes	3,924	-9,882	-8,739
Share-based compensation expenses	3,035	4,947	5,769
Excess tax benefits from share-based compensation	-7	-81	-49
Accounts receivable allowances	-2,186	2,814	-546
Noncash interest from discount on convertible debentures	0	0	229
Changes in operating assets and liabilities:	'	'	'
Accounts receivable	9,917	10,271	-11,999
Unbilled services	-2,997	-4,674	12,640
Prepaid expenses and other current assets, and other assets	-20,160	-19,870	-47
Accounts payable, accrued expenses, and other liabilities	11,114	-13,411	12,535
Net cash provided by (used in) operating activities	18,448	-8,525	30,031
INVESTING ACTIVITIES:	'	'	'
Consideration relating to acquisitions, net	-15,591	0	-844
Purchase of property and equipment	-2,816	-2,732	-8,246
Purchase of investments	0	-9,494	-61,049
Sale of investments	0	23,989	46,554
Collections on notes receivable	14	989	64
Net cash (used in) provided by investing activities	-18,393	12,752	-23,521
FINANCING ACTIVITIES:	'	'	'
Issuance of common stock, principally stock options exercises	207	647	620
Borrowings under line of credit	17,320	0	0
Payments under line of credit	-17,320	0	0
Payments on notes payable	-700	-650	-334
Extinguishment of convertible debentures	0	0	-21,880
Payments of debt issuance costs	-1,120	0	0
Tax withholding payment reimbursed by restricted shares	-730	-1,360	-1,146
Excess tax benefits from share-based compensation	7	81	49
Repurchase of common stock	-2,190	-9,062	-9,054
Repurchase of treasury stock by Neuco, Inc.	0	0	-33
Net cash used in financing activities	-4,526	-10,344	-31,778
Effect of foreign exchange rates on cash and cash equivalents	271	-19	-650
Net decrease in cash and cash equivalents	-4,200	-6,136	-25,918
Cash and cash equivalents at beginning of period	55,451	61,587	87,505
Cash and cash equivalents at end of period	51,251	55,451	61,587
Supplemental cash flow information:	'	'	'
Cash paid for taxes	2,887	8,718	18,744
Cash paid for interest	$339	$223	$558

CONSOLIDATED_STATEMENTS_OF_SHA

CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (USD $)	Total	CRA International, Inc. Shareholders' Equity	Common Stock	Receivable from Shareholder	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Noncontrolling Interest
In Thousands, except Share data, unless otherwise specified
BALANCE at Jan. 01, 2011	$255,424	$254,754	$103,067	($1,400)	$158,749	($5,662)	$670
BALANCE (in shares) at Jan. 01, 2011	'	'	10,567,052	'	'	'	'
Increase (Decrease) in Shareholders' Equity	'	'	'	'	'	'	'
Net income (loss)	16,945	16,851	'	'	16,851	'	94
Foreign currency translation adjustment	-676	-676	'	'	'	-676	'
Exercise of stock options	620	620	620	'	'	'	'
Exercise of stock options (in shares)	47,009	'	47,009	'	'	'	'
Share-based compensation expense for employees	5,696	5,696	5,696	'	'	'	'
Restricted shares vesting (in shares)	'	'	164,086	'	'	'	'
Redemption of vested employee restricted shares for tax withholding	-1,146	-1,146	-1,146	'	'	'	'
Redemption of vested employee restricted shares for tax withholding (in shares)	'	'	-50,724	'	'	'	'
Tax deficit on stock option exercises and restricted share vesting	-639	-639	-639	'	'	'	'
Notes receivable issued to shareholders	-36	-36	'	-36	'	'	'
Payments received on notes receivable from shareholders	1,200	1,200	'	1,200	'	'	'
Shares repurchased	-9,054	-9,054	-9,054	'	'	'	'
Shares repurchased (in shares)	-398,372	'	-398,372	'	'	'	'
Share-based compensation expense for non-employees	34	34	34	'	'	'	'
Equity transactions of noncontrolling interest	39	'	'	'	'	'	39
BALANCE at Dec. 31, 2011	268,407	267,604	98,578	-236	175,600	-6,338	803
BALANCE (in shares) at Dec. 31, 2011	'	'	10,329,051	'	'	'	'
Increase (Decrease) in Shareholders' Equity	'	'	'	'	'	'	'
Net income (loss)	-52,843	-52,990	'	'	-52,990	'	147
Foreign currency translation adjustment	1,950	1,950	'	'	'	1,950	'
Exercise of stock options	647	647	647	'	'	'	'
Exercise of stock options (in shares)	47,185	'	47,185	'	'	'	'
Share-based compensation expense for employees	4,868	4,868	4,868	'	'	'	'
Restricted shares vesting (in shares)	'	'	216,528	'	'	'	'
Redemption of vested employee restricted shares for tax withholding	-1,360	-1,360	-1,360	'	'	'	'
Redemption of vested employee restricted shares for tax withholding (in shares)	'	'	-69,207	'	'	'	'
Tax deficit on stock option exercises and restricted share vesting	-576	-576	-576	'	'	'	'
Payments received on notes receivable from shareholders	116	116	'	116	'	'	'
Shares repurchased	-9,062	-9,062	-9,062	'	'	'	'
Shares repurchased (in shares)	-466,109	'	-466,109	'	'	'	'
Share-based compensation expense for non-employees	79	79	79	'	'	'	'
Equity transactions of noncontrolling interest	8	'	'	'	'	'	8
BALANCE at Dec. 29, 2012	212,234	211,276	93,174	-120	122,610	-4,388	958
BALANCE (in shares) at Dec. 29, 2012	10,057,448	'	10,057,448	'	'	'	'
Increase (Decrease) in Shareholders' Equity	'	'	'	'	'	'	'
Net income (loss)	11,235	11,370	'	'	11,370	'	-135
Foreign currency translation adjustment	964	964	'	'	'	964	'
Exercise of stock options	207	207	207	'	'	'	'
Exercise of stock options (in shares)	13,389	'	13,389	'	'	'	'
Share-based compensation expense for employees	2,888	2,888	2,888	'	'	'	'
Restricted shares vesting (in shares)	'	'	134,384	'	'	'	'
Redemption of vested employee restricted shares for tax withholding	-730	-730	-730	'	'	'	'
Redemption of vested employee restricted shares for tax withholding (in shares)	'	'	-37,642	'	'	'	'
Tax deficit on stock option exercises and restricted share vesting	-254	-254	-254	'	'	'	'
Payments received on notes receivable from shareholders	120	120	'	120	'	'	'
Shares repurchased	-2,190	-2,190	-2,190	'	'	'	'
Shares repurchased (in shares)	-118,968	'	-118,968	'	'	'	'
Share-based compensation expense for non-employees	147	147	147	'	'	'	'
Equity transactions of noncontrolling interest	16	'	'	'	'	'	16
BALANCE at Dec. 28, 2013	$224,637	$223,798	$93,242	$0	$133,980	($3,424)	$839
BALANCE (in shares) at Dec. 28, 2013	10,048,611	'	10,048,611	'	'	'	'

Summary_of_Significant_Account

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 28, 2013
Summary of Significant Accounting Policies	'
Summary of Significant Accounting Policies	'
	1.     Summary of Significant Accounting Policies
	Description of Business
	CRA International, Inc. ("CRA") is a worldwide leading consulting services firm that applies advanced analytic techniques and in-depth industry knowledge to complex engagements for a broad range of clients. CRA offers services in two broad areas: litigation, regulatory, and financial consulting and management consulting. CRA operates in one business segment, which is consulting services. CRA operates its business under its registered trade name, Charles River Associates.
	Fiscal Year
	CRA's fiscal year end is the Saturday nearest December 31 of each year. CRA's fiscal years periodically contain 53 weeks rather than 52 weeks. Fiscal 2013, fiscal 2012, and fiscal 2011 were 52-week years.
	Principles of Consolidation
	The consolidated financial statements include the accounts of CRA and its wholly owned subsidiaries. In addition, as more fully explained below, the consolidated financial statements include CRA's interest in NeuCo, Inc. ("NeuCo"). All significant intercompany accounts have been eliminated.
	NeuCo Interest
	CRA's ownership interest in NeuCo is 55.89%. CRA's ownership interest has constituted control under GAAP for all periods presented. Therefore, NeuCo's financial results have been consolidated with CRA's and the portion of NeuCo's results allocable to its other owners is shown as "noncontrolling interest." NeuCo's revenues included in the CRA's consolidated statements of operations for fiscal 2013, fiscal 2012, and fiscal 2011 totaled approximately $5.1 million, $5.5 million, and $6.2 million, respectively. NeuCo's net loss included in CRA's consolidated statements of operations for fiscal 2013 was approximately $0.3 million. NeuCo's net income included in CRA's consolidated statements of operations for fiscal 2012 and fiscal 2011 was approximately $0.3 million and $0.2 million, respectively. NeuCo's net loss, net of amounts allocable to its other owners, included in CRA's consolidated statements of operations for fiscal 2013 was approximately $0.2 million. NeuCo's net income, net of amounts allocable to its other owners, included in CRA's consolidated statements of operations for fiscal 2012 and fiscal 2011 was approximately $0.2 million and $0.1 million, respectively. NeuCo's interim reporting schedule is based on calendar month-ends, and its fiscal year end is the last Saturday of November. CRA's quarterly results could include a few days reporting lag between CRA's quarter end and the most recent financial statements available from NeuCo. CRA does not believe that the reporting lag, if any, will have a significant impact on CRA's consolidated statements of operations or financial condition.
	Estimates
	The preparation of financial statements in conformity with accounting principles generally accepted in the U.S. requires management to make significant estimates and judgments that affect the reported amounts of assets and liabilities, and disclosure of contingent assets and liabilities, at the date of the financial statements, and the reported amounts of consolidated revenues and expenses during the reporting period. Estimates in these consolidated financial statements include, but are not limited to, accounts and unbilled receivable allowances, revenue recognition on fixed price contracts, depreciation of property and equipment, share-based compensation, valuation of acquired intangible assets, impairment of long lived assets and goodwill, accrued and deferred income taxes, valuation allowances on deferred tax assets, accrued compensation, accrued exit costs, and other accrued expenses. These items are monitored and analyzed by CRA for changes in facts and circumstances, and material changes in these estimates could occur in the future. Changes in estimates are recorded in the period in which they become known. CRA bases its estimates on historical experience and various other assumptions that CRA believes to be reasonable under the circumstances. Actual results may differ from those estimates if CRA's assumptions based on past experience or other assumptions do not turn out to be substantially accurate.
	Revenue Recognition
	CRA derives substantially all of its revenues from the performance of professional services. The contracts that CRA enters into and operates under specify whether the engagement will be billed on a time-and-materials or a fixed-price basis. These engagements generally last three to six months, although some of CRA's engagements can be much longer in duration. Each contract must be approved by one of CRA's vice presidents.
	CRA recognizes substantially all of its revenues under written service contracts with its clients when the fee is fixed or determinable, as the services are provided, and only in those situations where collection from the client is reasonably assured and sufficient contractual documentation has been obtained. In certain cases CRA provides services to its clients without sufficient contractual documentation, or fees are tied to performance-based criteria, which require CRA to defer revenue in accordance with U.S. GAAP. In these cases, these amounts are fully reserved until all criteria for recognizing revenue are met.
	CRA's revenues include projects secured by our non-employee experts as well as projects secured by our employees. CRA recognizes all project revenue on a gross basis based on the consideration of the criteria set forth in Accounting Standards Codification ("ASC") Topic 605-45, Principal Agent Considerations.
	Most of CRA's revenue is derived from time-and-materials service contracts. Revenues from time-and-materials service contracts are recognized as services are provided based upon hours worked and contractually agreed-upon hourly rates, as well as indirect fees based upon hours worked.
	Revenues from the majority of CRA's fixed-price engagements are recognized on a proportional performance method based on the ratio of costs incurred, substantially all of which are labor-related, to the total estimated project costs. CRA derived approximately 13%, 15%, and 22% of consolidated revenues from fixed-price engagements in fiscal 2013, fiscal 2012, and fiscal 2011, respectively. In general, project costs are classified as costs of services and are based on the direct salary of the consultants on the engagement plus all direct expenses incurred to complete the engagement, including any amounts billed to us by our non-employee experts. The proportional performance method is used because reasonably dependable estimates of the revenues and costs applicable to various stages of a contract can be made, based on historical experience and the terms set forth in the contract, and are indicative of the level of benefit provided to CRA's clients. Fixed-price contracts generally convert to time-and-materials contracts in the event the contract terminates. CRA's management maintains contact with project managers to discuss the status of the projects and, for fixed-price engagements, management is updated on the budgeted costs and resources required to complete the project. These budgets are then used to calculate revenue recognition and to estimate the anticipated income or loss on the project. Occasionally, CRA has been required to commit unanticipated additional resources to complete projects, which has resulted in lower than anticipated income or losses on those contracts. CRA may experience similar situations in the future. Provisions for estimated losses on contracts are made during the period in which such losses become probable and can be reasonably estimated. To date, such losses have not been significant.
	Revenues also include reimbursable expenses, which include travel and other out-of-pocket expenses, outside consultants, and other reimbursable expenses. Reimbursable expenses are as follows (in thousands):
		Year Ended			Year Ended			Year Ended
		December 28,			December 29,			December 31,
		2013			2012			2011
		(52 weeks)			(52 weeks)			(52 weeks)
	Reimbursable expenses	$	37,320		$	33,530		$	39,722
	CRA maintains accounts receivable allowances for estimated losses and disputed amounts resulting from clients' failure to make required payments. CRA bases its estimates on historical collection experience, current trends, and credit policy. In determining these estimates, CRA examines historical write-offs of its receivables and reviews client accounts to identify any specific customer collection issues. If the financial condition of CRA's customers were to deteriorate or disputes were to arise regarding the services provided, resulting in an impairment of their ability or intent to make payment, additional allowances may be required.
	Unbilled services represent revenue recognized by CRA for services performed but not yet billed to the client. Deferred revenue represents amounts billed or collected in advance of services rendered.
	CRA collects goods and services and value added taxes from customers and records these amounts on a net basis, which is within the scope of ASC Topic 605-45, Principal Agent Considerations.
	Cash Equivalents
	Cash equivalents consist principally of money market funds and commercial paper with maturities of three months or less when purchased. As of December 28, 2013, a substantial portion of CRA's cash accounts was concentrated at a single financial institution, which potentially exposes CRA to credit risks. The financial institution has a short-term credit rating of A-2 by Standard & Poor's ratings services. CRA has not experienced any losses related to such accounts. CRA does not believe that there is significant risk of non-performance by the financial institution and the cash on deposit is fully liquid. CRA continually monitors the credit ratings of the institution.
	The carrying amounts of these instruments classified as cash equivalents are stated at amortized cost, which approximates fair value because of their short-term maturity.
	Fair Value of Financial Instruments
	CRA's financial instruments, including cash, cash equivalents, accounts receivable, loans and advances from employees and non-employee experts, accounts payable, and accrued expenses, are carried at cost, which approximates their fair value because of the short-term maturity of these instruments or because their stated interest rates are indicative of market interest rates.
	Goodwill
	In accordance with ASC Topic 350, "Intangibles—Goodwill and Other", goodwill is not subject to amortization, but is monitored at least annually for impairment, or more frequently, as necessary, if events or circumstances exist that would more likely than not reduce the fair value of the reporting unit below its carrying amount. For the CRA's goodwill impairment analysis, CRA operates under one reporting unit. Under ASC Topic 350, in performing the first step of the goodwill impairment testing and measurement process, CRA compares its entity-wide estimated fair value to net book value to identify potential impairment. Management estimates the entity-wide fair value utilizing CRA's market capitalization, plus an appropriate control premium. Market capitalization is determined by multiplying the shares outstanding on the test date by the market price of CRA's common stock on that date. CRA has utilized a control premium which considers appropriate industry, market and other pertinent factors, including indications of such premiums from data on recent acquisition transactions. If the fair value of CRA is less than its net book value, the second step is performed to determine if goodwill is impaired. If CRA determines through the impairment evaluation process that goodwill has been impaired, an impairment charge would be recorded in the consolidated statement of operations.
	There were no impairment losses related to goodwill during fiscal 2013 as there were no events or circumstances that would more likely than not reduce CRA's fair value below its carrying amount.
	When CRA performed its annual impairment test in the fourth quarter of fiscal 2012, its net book value exceeded its market capitalization plus an estimated control premium. Therefore, CRA was required to perform the second step of the goodwill impairment test. In this step, CRA's fair value is allocated among all of its assets and liabilities, including any unrecognized intangible assets, in a hypothetical analysis that calculates the implied fair value of goodwill in the same manner as if CRA were being acquired in a business acquisition. If the implied fair value of goodwill is less than the recorded goodwill, an impairment charge is recorded for the difference. During the process of conducting the second step of the annual goodwill impairment test in the fourth quarter of fiscal 2012, CRA identified significant unrecognized intangible assets. The combination of these hypothetical unrecognized intangible assets and other hypothetical unrecognized fair value changes to the carrying values of other assets and liabilities, together with the lower fair value calculated in the first step of the annual impairment test, resulted in a goodwill impairment charge of $71.4 million in the fourth quarter of fiscal 2012.
	The re-measurement of goodwill is classified as a Level 3 fair value assessment due to the significance of unobservable inputs developed using CRA-specific information. CRA used a combination of the income, cost and market approach techniques to determine the fair value of its assets and liabilities. The fair value adjustment to goodwill was computed as the difference between CRA's fair value and the fair value of underlying assets and liabilities. The unobservable inputs used to determine the fair value of the underlying assets and liabilities were based on CRA-specific information such as estimates of revenue and cost growth rates, profit margins, discount rates, and cost estimates.
	Intangible Assets
	Intangible assets that are separable from goodwill and have determinable useful lives are valued separately and amortized over their estimated useful lives. Intangible assets consist of non-competition agreements, customer relationships, customer lists, developed technology, and trademarks, all of which are generally amortized on a straight-line basis over their remaining useful lives of four to ten years.
	Property and Equipment
	Property and equipment are recorded at cost. Depreciation is calculated using the straight-line method based on the estimated useful lives of three years for computer equipment, three to ten years for computer software, and ten years for furniture and fixtures. Amortization of leasehold improvements is calculated using the straight-line method over the shorter of the lease term or the estimated useful life of the leasehold improvements. Expenditures for maintenance and repairs are expensed as incurred. Expenditures for renewals and betterments are capitalized.
	Leases and Deferred Rent
	CRA leases all of its office space. Leases are evaluated and classified as operating or capital leases for financial reporting purposes. For leases that contain rent escalations and rent holidays, CRA records the total rent payable during the lease term, as determined above, on a straight-line basis over the term of the lease and records the difference between the rents paid and the straight-line rent as deferred rent. Additionally, any tenant improvement allowances received from the lessor are recorded as a reduction to deferred rent.
	Impairment of Long-Lived Assets
	CRA reviews the carrying value of its long-lived assets (primarily property and equipment and intangible assets) to assess the recoverability of these assets whenever events or circumstances indicate that impairment may have occurred. Factors CRA considers important that could trigger an impairment review include the following:
	•
	a significant underperformance relative to expected historical or projected future operating results;
	•
	a significant change in the manner of CRA's use of the acquired asset or the strategy for CRA's overall business; and
	•
	a significant negative industry or economic trend.
	If CRA determines that an impairment review is required, CRA would review the expected future undiscounted cash flows to be generated by the assets or asset groups. If CRA determines that the carrying value of long-lived assets or asset groups may not be recoverable, CRA would measure any impairment based on a projected discounted cash flow method using a discount rate determined by CRA to be commensurate with the risk inherent in CRA's current business model. If impairment is indicated through this review, the carrying amount of the assets would be reduced to their estimated fair value.
	Concentration of Credit Risk
	CRA's billed and unbilled receivables consist of receivables from a broad range of clients in a variety of industries located throughout the U.S. and in other countries. CRA performs a credit evaluation of its clients to minimize its collectability risk. Periodically, CRA will require advance payment from certain clients. However, CRA does not require collateral or other security. CRA maintains accounts receivable allowances for estimated losses and disputed amounts resulting from clients' failures to make required payments. CRA bases its estimates on historical collection experience, current trends, and credit policy. In determining these estimates, CRA examines historical write-offs of its receivables and reviews client accounts to identify any specific customer collection issues. If the financial condition of any of CRA's customers were to deteriorate, resulting in an impairment of their ability or intent to make payment, additional allowances may be required.
	A rollforward of the accounts receivable allowances is as follows (in thousands):
		Fiscal			Fiscal
		Year			Year
		2013			2012
	Balance at beginning of period	$	9,459		$	6,548
	Change related to NeuCo		(2	)		—
	Additions charged to revenues		5,644			6,808
	Amounts written off		(7,891	)		(3,897	)
	Balance at end of period	$	7,210		$	9,459
	Amounts deemed uncollectible are recorded as a reduction to revenues.
Share-Based Compensation
CRA accounts for equity-based compensation using a fair value based recognition method. Under the fair value recognition requirements of ASC Topic 718, "Compensation-Stock Compensation" ("ASC Topic 718"), share-based compensation cost is estimated at the grant date based on the fair value of the award and is recognized as expense over the requisite service period of the award. The amount of share-based compensation expense recognized at any date must at least equal the portion of grant date value of the award that is vested at that date.
For share-based awards granted to non-employee experts, CRA accounts for the compensation under variable accounting in accordance with ASC Topic 718 and ASC Topic 505-50, "Equity-Based Payments to Non-Employees" (formerly Emerging Issues Task Force 96-18, "Accounting for Equity Instruments That Are Issued to Other Than Employees for Acquiring, or in Conjunction with Selling, Goods or Services"), and recognizes the cost over the related vesting period. For performance-vesting restricted stock units awarded to employees, CRA accounts for the compensation under variable accounting in accordance with ASC Topic 718, and recognizes the cost over the related vesting period.
Income Taxes
CRA accounts for income taxes using the asset and liability method of accounting for income taxes. Deferred tax assets and liabilities are recognized based upon anticipated future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective income tax bases, and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. A valuation allowance is recorded to reduce the carrying amounts of deferred tax assets if it is more likely than not that such assets will not be realized.
In addition, the calculation of CRA's tax liabilities involves dealing with uncertainties in the application of complex tax regulations in several different tax jurisdictions. CRA records liabilities for estimated tax obligations resulting in a provision for taxes that may become payable in the future, in accordance with ASC Topic 740-10, "Income Taxes," which prescribes a recognition threshold and measurement attribute for the financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return and also provides guidance on derecognition, classification, interest and penalties, accounting in interim periods, and disclosure. CRA includes accrued interest and penalties, if any, related to uncertain tax positions in income tax expense.
Foreign Currency Translation
Balance sheet accounts of CRA's foreign subsidiaries are translated into U.S. dollars at year-end exchange rates and operating accounts are translated at average exchange rates for each year. The resulting translation adjustments are recorded in shareholders' equity as a component of accumulated other comprehensive income (loss). Foreign currency transactions are translated at current exchanges rates, with adjustments recorded in the statement of operations. The effect of transaction gains and losses recorded in income (loss) before (provision) benefit for income taxes amounted to losses of $0.2 million, $0.2 million, and $0.4 million for fiscal 2013, fiscal 2012, and fiscal 2011, respectively.
Recent Accounting Standards
Presentation of Unrecognized Tax Benefits
In July 2013, the Financial Accounting Standards Board (the "FASB") issued Accounting Standards Update ("ASU") No. 2013-11, Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists ("ASU 2013-11") to clarify the presentation of current and deferred income taxes on the balance sheet. Under ASU 2013-11, companies generally must present an unrecognized tax benefit, or a portion of an unrecognized tax benefit, for an NOL carryforward, similar tax loss, or tax credit carryforward using the "net presentation" approach as a reduction of a deferred tax asset, with some allowed exceptions. ASU 2013-11 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2013. Early adoption is permitted and entities may choose to apply the amendments retrospectively to each prior reporting period presented. CRA believes the adoption of ASU 2013-11 will have no impact on its financial position, results of operations, cash flows, or disclosures.
Comprehensive Income
In February 2013, the FASB issued ASU No. 2013-02, Comprehensive Income (Topic 220): Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income ("ASU 2013-02"). ASU 2013-02 requires an entity disclose in a single location (either on the face of the financial statement that reports net income or in the notes) the effects of reclassifications out of accumulated other comprehensive income. For items reclassified out of accumulated other comprehensive income and into net income in their entirety, entities must disclose the effect of the reclassification on each affected net income item. For accumulated other comprehensive income reclassification items that are not reclassified in their entirety into net income, entities must provide a cross reference to other required U.S. GAAP disclosures. There is no change in the requirement to present the components of net income and other comprehensive income in either a single continuous statement or two separate consecutive statements. ASU 2013-02 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2012 and should be applied prospectively. CRA's adoption of ASU 2013-02 in the first quarter of fiscal 2013 had no impact on its financial position, results of operations, cash flows, or disclosures.
Cumulative Translation Adjustment
In March 2013, the FASB issued ASU No. 2013-05, Parent's Accounting for the Cumulative Translation Adjustment upon Derecognition of Certain Subsidiaries or Groups of Assets within a Foreign Entity or of an Investment in a Foreign Entity ("ASU 2013-05"). ASU 2013-05 addresses the accounting for the cumulative translation adjustment when a parent either sells a part or all of its investment in a foreign entity or no longer holds a controlling financial interest in a subsidiary or group of assets that is a nonprofit activity or a business within a foreign entity. ASU 2013-05 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2013 and should be applied prospectively. Early adoption is permitted. CRA believes the adoption of ASU 2013-05 will have no impact on its financial position, results of operations, cash flows, or disclosures.
Intangibles
In July 2012, the FASB issued ASU No. 2012-02, Intangibles—Goodwill and Other (Topic 350): Testing Indefinite-Lived Intangible Assets for Impairment ("ASU 2012-02") to simplify the guidance for testing the decline in the realizable value (impairment) of indefinite-lived intangible assets other than goodwill. Under former guidance, an organization was required to test an indefinite-lived intangible asset for impairment on at least an annual basis by comparing the fair value of the asset with its carrying amount. If the carrying amount of an indefinite-lived intangible asset exceeded its fair value, an impairment loss was recognized in an amount equal to the difference. ASU 2012-02 allows an organization the option to first assess qualitative factors to determine whether it is necessary to perform the quantitative impairment test. An organization electing to perform a qualitative assessment is no longer required to calculate the fair value of an indefinite-lived intangible asset unless the organization determines, based on a qualitative assessment, that it is "more likely than not" that the asset is impaired. ASU 2012-02 was effective for annual and interim impairment tests performed for fiscal years beginning after September 15, 2012. CRA's adoption of ASU 2012-02 in fiscal 2013 had no impact on its financial position, results of operations, cash flows, or disclosures.

Business_Acquisition

Business Acquisition	12 Months Ended
	Dec. 28, 2013
Business Acquisition	'
Business Acquisition	'
	2.     Business Acquisition
	On January 31, 2013, CRA announced that an approximately 40-person litigation consulting team joined CRA, effective February 1, 2013. Under an agreement to hire the team, CRA accelerated the previously announced start dates of certain key personnel from May 2013. Under the terms of the transaction, CRA acquired certain intangible assets, accounts receivable, and certain client projects currently underway. The fair values of the assets acquired and the liabilities assumed as part of the acquisition will be finalized as CRA receives other information relevant to the acquisition and completes its analysis of other transaction-related costs. The acquisition was not material. The acquisition has been accounted for under the purchase method of accounting, and the results of operations have been included in the accompanying statements of operations from the date of acquisition.

Prepaid_Expenses_and_Other_Cur

Prepaid Expenses and Other Current Assets, and Other Assets	12 Months Ended
	Dec. 28, 2013
Prepaid Expenses and Other Current Assets, and Other Assets	'
Prepaid Expenses and Other Current Assets, and Other Assets	'
	3.     Prepaid Expenses and Other Current Assets, and Other Assets
	Prepaid expenses and other current assets consist of the following (in thousands):
		December 28,		December 29,
		2013		2012
	Term loans to employees and non-employee experts	$	1,764	$	8,614
	Other		10,011		14,387
	Total	$	11,775	$	23,001
	Other assets consist of the following (in thousands):
		December 28,		December 29,
		2013		2012
	Forgivable loans to employees and non-employee experts	$	51,083	$	15,448
	Other		3,538		6,223
	Total	$	54,621	$	21,671
	In order to attract and retain highly skilled professionals, CRA may issue forgivable loans or term loans to employees and non-employee experts which are classified in "prepaid expenses and other current assets" and "other assets" on the accompanying balance sheets as of December 28, 2013 and December 29, 2012. The forgivable loans have terms that are generally between three and eight years. The principal amount of forgivable loans and accrued interest is forgiven by CRA over the term of the loans, so long as the employee or non-employee expert continues employment or affiliation with CRA and complies with certain contractual requirements. The expense associated with the forgiveness of the principal amount of the loans is recorded as compensation expense over the service period, which is consistent with the term of the loans. During fiscal 2013 and fiscal 2012, CRA issued approximately $38.8 million and $20.7 million, respectively, in forgivable loans to employees and non-employee experts for future service. As of December 28, 2013, CRA had obligations to issue approximately $5.0 million in forgivable loans to future employees for future service, which are included in the $51.1 million of such loans reported as of December 28, 2013 in the table above. The $5.0 million in loans were issued, and the corresponding payments were made, in the first quarter of fiscal 2014.

Goodwill_and_Intangible_Assets

Goodwill and Intangible Assets	12 Months Ended
	Dec. 28, 2013
Goodwill and Intangible Assets	'
Goodwill and Intangible Assets	'
	4.     Goodwill and Intangible Assets
	The changes in the carrying amount of goodwill for fiscal 2013 and fiscal 2012 are as follows (in thousands):
		Goodwill,			Accumulated			Goodwill,
		gross			impairment			net
					losses
	Balance at December 29, 2012	$	142,658		$	(71,893	)	$	70,765
	Goodwill adjustments related to acquisitions		10,563			—			10,563
	Goodwill adjustments related to NeuCo		(63	)		—			(63	)
	Effect of foreign currency translation		308			—			308
	Balance at December 28, 2013	$	153,466		$	(71,893	)	$	81,573
		Goodwill,			Accumulated			Goodwill,
		gross			impairment			net
					losses
	Balance at December 31, 2011	$	141,153		$	(499	)	$	140,654
	Goodwill impairment		—			(71,394	)		(71,394	)
	Goodwill adjustments related to sale of practice		(29	)		—			(29	)
	Effect of foreign currency translation		1,534			—			1,534
	Balance at December 29, 2012	$	142,658		$	(71,893	)	$	70,765
	There were no impairment losses related to goodwill during fiscal 2013. When CRA performed its annual impairment test in the fourth quarter of fiscal 2012, its net book value exceeded its market capitalization plus an estimated control premium. Therefore, CRA was required to perform the second step of the goodwill impairment test, which resulted in a goodwill impairment charge of $71.4 million. CRA recorded this goodwill impairment charge in the fourth quarter of fiscal 2012.
	Intangible assets that are separable from goodwill and have determinable useful lives are valued separately and amortized over their expected useful lives. There were no impairment losses related to intangible assets during fiscal 2013, fiscal 2012, or fiscal 2011.
	The components of acquired identifiable intangible assets are as follows (in thousands):
		December 28,			December 29,
		2013			2012
	Non-competition agreements, net of accumulated amortization of $3,802, and $3,311, respectively	$	598		$	1,047
	Customer relationships, net of accumulated amortization of $3,550 and $2,840, respectively		3,909			691
	Other intangible assets, net of accumulated amortization of $1,040, and $971, respectively		30			96
		$	4,537		$	1,834
	Amortization of intangible assets was $1.2 million, $0.8 million, and $0.9 million in fiscal 2013, fiscal 2012, and fiscal 2011, respectively. Amortization of intangible assets held at December 28, 2013 for the next five fiscal years is expected to be as follows (in thousands):
	Fiscal Year	Amortization
		Expense
	2014	$	1,111
	2015		768
	2016		579
	2017		537
	2018		512
		$	3,507

Property_and_Equipment

Property and Equipment	12 Months Ended
	Dec. 28, 2013
Property and Equipment	'
Property and Equipment	'
	5.     Property and Equipment
	Property and equipment consist of the following (in thousands):
		December 28,			December 29,
		2013			2012
	Computer, office equipment and software	$	25,034		$	24,867
	Leasehold improvements		21,388			20,622
	Furniture		7,788			7,886
			54,210			53,375
	Accumulated depreciation and amortization		(38,555	)		(35,395	)
		$	15,655		$	17,980
	Depreciation expense, including amounts recorded in costs of services, was $5.2 million, $5.0 million, and $4.1 million, in fiscal 2013, fiscal 2012, and fiscal 2011, respectively.

Accrued_Expenses

Accrued Expenses	12 Months Ended
	Dec. 28, 2013
Accrued Expenses	'
Accrued Expenses	'
	6.     Accrued Expenses
	Accrued expenses consist of the following (in thousands):
		December 28,		December 29,
		2013		2012
	Compensation and related expenses	$	51,960	$	40,329
	Income taxes payable		3,503		626
	Other		10,194		4,350
		$	65,657	$	45,305
	As of December 28, 2013 and December 29, 2012, approximately $40 million and $28 million of accrued bonuses for fiscal 2013 and fiscal 2012, respectively, were included above in "Compensation and related expenses". Additionally, as of December 28, 2013, CRA had obligations to issue approximately $5.0 million in forgivable loans to future employees for future service, which are included in "Other" in the table above. The $5.0 million in loans were issued, and the corresponding payments were made, in the first quarter of fiscal 2014.

Credit_Agreement

Credit Agreement	12 Months Ended
	Dec. 28, 2013
Credit Agreement	'
Credit Agreement	'
	7.     Credit Agreement
	On April 24, 2013, CRA entered into a credit agreement that provides CRA with a $125.0 million revolving credit facility and a $15 million sublimit for the issuance of letters of credit. CRA may use the proceeds of the revolving credit loans for working capital and other general corporate purposes. CRA may repay any borrowings under the revolving credit facility at any time, but no later than April 24, 2018. Upon entering into the agreement, CRA borrowed $15.0 million under the revolving credit facility, which it used, together with cash on hand, to repay in full all indebtedness outstanding under CRA's previous credit agreement, whereupon such agreement was terminated. CRA also borrowed an additional $2.3 million during the second quarter of fiscal 2013 under the multi-currency portion of the credit agreement. There was no amount outstanding under this revolving line of credit as of December 28, 2013, as CRA repaid these borrowings before the end of the third quarter of fiscal 2013.
	As of December 28, 2013, the amount available under this revolving line of credit was reduced by certain letters of credit outstanding, which amounted to $0.4 million. Borrowings under the revolving credit facility bear interest at a rate per annum of either (i) the adjusted base rate, as defined in the credit agreement, plus an applicable margin, which varies between 0.50% and 1.50% depending on CRA's total leverage ratio as determined under the credit agreement, or (ii) the adjusted eurocurrency rate, as defined in the credit agreement, plus an applicable margin, which varies between 1.50% and 2.50% depending on CRA's total leverage ratio. CRA is required to pay a fee on the unused portion of the revolving credit facility at a rate per annum that varies between 0.25% and 0.375% depending on its total leverage ratio. Borrowings under the credit facility are secured by 100% of the stock of certain of CRA's U.S. subsidiaries and 65% of the stock of certain of its foreign subsidiaries, which represent approximately $6.5 million in net assets as of December 28, 2013.
	Under the credit agreement, CRA must comply with various financial and non-financial covenants. Compliance with these financial covenants is tested on a fiscal quarterly basis. Any indebtedness outstanding under the credit facility may become immediately due and payable upon the occurrence of stated events of default, including CRA's failure to pay principal, interest or fees or a violation of any financial covenant. The financial covenants require CRA to maintain a consolidated interest expense to adjusted consolidated EBITDA ratio of more than 2.5 to 1.0 and to comply with a consolidated debt to adjusted consolidated EBITDA ratio of not more than 3.0 to 1.0. The non-financial covenant restrictions of the senior credit agreement include, but are not limited to, CRA's ability to incur additional indebtedness, engage in acquisitions or dispositions, and enter into business combinations.

Employee_Benefit_Plans

Employee Benefit Plans	12 Months Ended
	Dec. 28, 2013
Employee Benefit Plans	'
Employee Benefit Plans	'
	8.     Employee Benefit Plans
	CRA maintains qualified defined-contribution plans under Section 401(k) of the Internal Revenue Code, covering substantially all U.S. employees who meet specified age and service requirements. Company contributions are made at the discretion of CRA, and cannot exceed the maximum amount deductible under applicable provisions of the Internal Revenue Code. Company contributions under these plans amounted to approximately $1.7 million, $1.8 million, and $2.7 million for fiscal 2013, fiscal 2012, and fiscal 2011, respectively.

Leases

Leases	12 Months Ended
	Dec. 28, 2013
Leases	'
Leases	'
	9.     Leases
	At December 28, 2013, CRA had the following minimum rental commitments for office space and equipment leases, all of which are under non-cancelable operating leases (in thousands):
	Fiscal Year	Rental
		Commitments
	2014	$	13,912
	2015		8,824
	2016		4,038
	2017		1,908
	2018		850
	Thereafter		17
		$	29,549
	Future minimum rentals under sublease arrangements		(2,918	)
		$	26,631
	Certain office leases contain renewal options that CRA may exercise at its discretion, which were not included in the amounts above. Rent expense was approximately $9.6 million in fiscal 2013, $12.4 million in fiscal 2012, and $13.6 million in fiscal 2011. Included in rent expense were $0.9 million and $1.0 million in restructuring charges in fiscal 2012 and fiscal 2011, respectively. There were no restructuring charges during fiscal 2013.
	CRA is party to standby letters of credit with its bank in support of the minimum future lease payments under leases for office space amounting to $0.4 million as of December 28, 2013.
	See Note 18 for subsequent event related to operating lease obligations.

Net_Income_Loss_Per_Share

Net Income (Loss) Per Share	12 Months Ended
	Dec. 28, 2013
Net Income (Loss) Per Share	'
Net Income (Loss) Per Share	'
	10.   Net Income (Loss) Per Share
	Basic net income (loss) per share represents net income (loss) divided by the weighted average shares of common stock outstanding during the period. Diluted net income per share represents net income divided by the weighted average shares of common stock and common stock equivalents, if applicable, outstanding during the period. Common stock equivalents arise from stock options and unvested shares of restricted stock, using the treasury stock method. Under the treasury stock method, the amount CRA would receive on the exercise of stock options and the vesting of shares of restricted stock, the amount of compensation cost for future service that CRA has not yet recognized, and the amount of tax benefits that would be recorded in common stock when these stock options and shares of restricted stock become deductible are assumed to be used to repurchase shares at the average share price over the applicable fiscal period, and these repurchased shares are netted against the shares underlying these stock options and these unvested shares of restricted stock. A reconciliation of basic to diluted weighted average shares of common stock outstanding is as follows (in thousands):
		Fiscal Year		Fiscal Year		Fiscal Year
		2013		2012		2011
	Basic weighted average shares outstanding		10,084		10,167		10,555
	Common stock equivalents:
	Stock options and restricted stock		89		—		184
	Diluted weighted average shares outstanding		10,173		10,167		10,739
	For fiscal 2013, fiscal 2012, and fiscal 2011, certain share-based awards, which amounted to 1,138,411, 1,947,992, and 1,045,351 shares, respectively, were excluded from the calculation of common stock equivalents for purposes of computing diluted weighted average shares outstanding because they were anti-dilutive. These share-based awards were anti-dilutive because their exercise price exceeded the average market price over the applicable period. Additionally, approximately 140,000 common stock equivalents were excluded from diluted weighted average shares outstanding for fiscal 2012 because they were anti-dilutive as CRA had a net loss for that period.

Common_Stock

Common Stock	12 Months Ended
	Dec. 28, 2013
Common Stock	'
Common Stock	'
	11.   Common Stock
	Share-Based Compensation.    Approximately $2.9 million, $4.9 million, and $5.7 million of share-based compensation expense was recorded in fiscal 2013, fiscal 2012, and fiscal 2011, respectively, as an increase to common stock for share-based payment awards made to CRA's employees and directors, based on the estimated grant date fair values of stock options and shares of restricted stock vesting during the period.
	CRA also recorded $147,000, $79,000, and $34,000 for fiscal 2013, fiscal 2012, and fiscal 2011, respectively, in shared-based compensation expense for grants to non-employee experts.
	Restricted Share Vesting.    In fiscal 2013, fiscal 2012, and fiscal 2011, 134,384, 216,528, and 164,086 shares of restricted stock vested, respectively. CRA redeemed 37,642, 69,207, and 50,724 of these shares from their holders in order to pay $0.7 million, $1.4 million, and $1.1 million, respectively, of employee tax withholdings.
	Common Stock Repurchases and Retirements.    On July 6, 2010, CRA announced that its Board of Directors approved a share repurchase program of up to $5 million of CRA's common stock. On August 30, 2011, February 22, 2012 and August 10, 2012, the Board of Directors authorized the repurchase of up to an additional $7.5 million, $4.45 million, and $5.0 million, respectively, of CRA's common stock under these programs.
	During fiscal 2013, CRA repurchased and retired 118,968 shares of its common stock under these programs at an aggregate price of approximately $2.2 million, resulting in approximately $1.4 million available for future repurchases as of December 28, 2013. During fiscal 2012, CRA repurchased and retired 466,109 shares of its common stock under these programs at an aggregate price of approximately $9.1 million. During fiscal 2011, CRA repurchased and retired 398,372 shares of its common stock under these programs at an aggregate price of approximately $9.1 million. CRA records the retirement of its repurchased common stock as a reduction to common stock.
	On February 13, 2014, CRA announced that its Board of Directors approved a share repurchase program of up to an additional $15.0 million of CRA's common stock.
	During fiscal 2013, fiscal 2012, and fiscal 2011, CRA did not repurchase any shares of its common stock from non-employee experts and employees based on contractual rights of first purchase contained in their stock purchase agreement with CRA.
	Exercise of Stock Options.    During fiscal 2013, 13,389 options were exercised for $0.2 million of proceeds. During fiscal 2012, 47,185 options were exercised for $0.6 million of proceeds. During fiscal 2011, 47,009 options were exercised for $0.6 million of proceeds.
	Tax Deficit on Stock Option Exercises and Restricted Share Vesting.    CRA recorded tax deficits on stock options exercises and vesting of shares of restricted stock as a decrease to common stock in fiscal 2013, fiscal 2012, and fiscal 2011, totaling $0.3 million, $0.6 million, and $0.6 million, respectively.

ShareBased_Compensation

Share-Based Compensation	12 Months Ended
	Dec. 28, 2013
Share-Based Compensation	'
Share-Based Compensation	'
	12.   Share-Based Compensation
	CRA recorded $2.9 million, $4.9 million, and $5.7 million of compensation expense for fiscal 2013, fiscal 2012, and fiscal 2011, respectively, for share-based awards consisting of stock options, shares of restricted stock and time-vesting restricted stock units issued to employees and directors based on their respective estimated grant date fair values. Compensation expense also includes performance-vesting restricted stock units issued to employees that are accounted for under variable accounting in accordance with ASC Topic 718.
	Compensation expense, net of tax, was $1.9 million, $3.0 million, and $3.5 million in fiscal 2013, fiscal 2012, and fiscal 2011, respectively, for share-based awards made to CRA's employees and directors consisting of stock options, shares of restricted stock, and time-vesting restricted stock units issued to employees and directors based on their respective estimated grant date fair values and for performance-vesting restricted stock units issued to employees that are accounted for under variable accounting.
	In addition, CRA recorded $87,000, $47,000, and $20,000 of share-based compensation expense, net of tax, during fiscal 2013, fiscal 2012, and fiscal 2011, respectively, for share-based awards consisting of stock options and shares of restricted stock issued to non-employees (other than directors).
	The weighted average fair market value using the Black-Scholes option-pricing model of the stock options granted in fiscal 2013, and fiscal 2011 was $7.77 and $10.01, respectively. There were no stock options granted during fiscal 2012. The fair market value of the stock options at the date of grant was estimated using the Black-Scholes option-pricing model with the following weighted average assumptions:
		2013			2011
	Risk-free interest rate		1.4	%		1	%
	Expected volatility		47	%		54	%
	Weighted average expected life (in years)		5			5
	Expected dividends		—			—
	The risk-free interest rate is based on U.S. Treasury interest rates whose term is consistent with the expected life of the stock options. Expected volatility and expected life are based on CRA's historical experience. Expected dividend yield was not considered in the option-pricing formula because CRA does not pay dividends and has no current plans to do so in the future. The forfeiture rate used was based upon historical experience. CRA may adjust the estimated forfeiture rate based upon actual experience.
	CRA maintains share-based compensation plans that use restricted stock, stock options, restricted stock units, as well as an employee stock purchase plan, to provide incentives to its directors, employees and independent contractors.
	CRA's Amended and Restated 2006 Equity Incentive Plan, as amended (the "2006 Incentive Plan"), authorizes the grant of a variety of incentive and performance awards to CRA's directors, employees and independent contractors, including incentive stock options, nonqualified stock options, restricted stock awards, restricted stock unit awards, performance awards and other share-based awards. Each share of CRA's common stock issued pursuant to an award (other than a stock option) granted under the 2006 Incentive Plan on or after April 30, 2010 counts as 1.83 shares against the maximum number of shares issuable under the plan, as does any restricted stock unit or other performance award granted under the plan on or after April 30, 2010 to the extent that shares of CRA's common stock were or will be used for measurement purposes. This "fungibility ratio" with respect to shares of CRA's common stock issued pursuant to awards (other than stock options) granted under the plan, as well as restricted stock unit and other performance awards granted under the plan to the extent that shares of CRA's common stock are used for measurement purposes, was 2.2 for grants made on or after March 12, 2008 and before April 30, 2010 and 1.8 for grants made before March 12, 2008. The maximum number of shares issuable under the 2006 Incentive Plan is 4,874,000, consisting of (1) 500,000 shares initially reserved for issuance under the 2006 Incentive Plan, (2) 1,000,000 shares that either remained for future awards under our 1998 Incentive and Nonqualified Stock Option Plan (the "1998 Plan") on April 21, 2006, the date CRA's shareholders initially approved the 2006 Incentive Plan, or were subject to stock options issued under the 1998 Plan that were forfeited or terminated after April 21, 2006, (3) 210,000 shares approved by CRA's shareholders in 2008, (4) 1,464,000 shares approved by CRA's shareholders in 2010, and (5) the 1,700,000 shares that CRA has determined to use of the 2,500,000 shares approved by CRA's shareholders in 2012.
	During fiscal 2009, CRA implemented a long-term incentive program ("LTIP") for certain key employees. Under this program, participants may receive a mixture of stock options, restricted stock units, and performance-vesting restricted stock units. The program is designed to reward key employees and provide participants the opportunity to share in the long-term growth of CRA. CRA has granted options, restricted stock units, and performance-vesting restricted stock units under this program during fiscal 2009 through fiscal 2013, except fiscal 2012. The awards were granted under the 2006 Incentive Plan and are included in the discussion below. The following is a rollforward of the maximum number of shares issuable under the 2006 Incentive Plan as of December 28, 2013:
		Actual			Shares Using
		Shares			Fungibility Ratio
	Maximum shares of common stock issuable under the 2006 Incentive Plan					4,874,000
	Restricted shares or units granted/reserved through March 12, 2008		471,827			(849,289	)
	Restricted shares or units granted/reserved from March 12, 2008 to April 29, 2010		352,932			(776,450	)
	Restricted shares or units granted/reserved on or after April 30, 2010		1,196,776			(2,190,100	)
	Cancellation of restricted shares or units through March 12, 2008		91,277			164,299
	Cancellation of restricted shares or units from March 12, 2008 to April 29, 2010		91,964			202,321
	Cancellation of restricted shares or units on or after April 30, 2010		302,374			553,345
	Options granted					(916,118	)
	Options cancelled					183,208
	Options forfeited					10,000
	Shares available for grant under the 2006 Incentive Plan					1,255,216
	Under the 1998 Plan, 3,839,216 options to purchase shares have been granted. With the adoption of the 2006 Incentive Plan, no new options will be granted under the 1998 Plan. Under the terms of the 1998 Plan, options have been granted at an exercise price equal to the fair market value of the shares of common stock at the date of grant. Vesting terms were determined at the discretion of the Board of Directors and generally range from immediate vesting to vesting at various rates up to five years. In general, stock options terminate 7 to 10 years after the date of grant.
	In addition, under CRA's 2004 Nonqualified Inducement Stock Option Plan, options to purchase 359,420 shares have been granted. With the adoption of the 2006 Incentive Plan, no new stock options will be granted under the 2004 Nonqualified Inducement Stock Option Plan.
	Under CRA's 2009 Nonqualified Inducement Stock Option Plan, options to purchase 200,000 shares have been granted. There are a maximum of 250,000 shares available for issuance pursuant to stock option grants under the 2009 Nonqualified Inducement Stock Option Plan. There are an additional 50,000 stock options available for grant under this plan. Each stock option vests over four years, has a term of seven years, and an exercise price equal to $50.00 per share.
	A summary of option activity from all plans is as follows:
		Options			Weighted			Weighted Average		Aggregate
					Average			Remaining		Intrinsic
					Exercise			Contractual		Value
					Price			Term
										(in thousands)
	Outstanding at December 29, 2012		1,169,478		$	32.33
	Fiscal 2013:
	Granted		262,463			18.48
	Exercised		(13,389	)		15.44
	Forfeited		(126,203	)		24.84
	Outstanding at December 28, 2013		1,292,349			30.43			3.38	$	585
	Options exercisable at December 28, 2013		890,671		$	35.28			2.15	$	—
	The aggregate intrinsic value of stock options exercised in fiscal 2013, fiscal 2012, and fiscal 2011 was approximately $0.1 million, $0.4 million, and $0.6 million, respectively. The following table summarizes stock options outstanding and stock options exercisable as of December 28, 2013:
		Options Outstanding								Options Exercisable
	Range of Exercise Prices	Number			Weighted-Average			Weighted-Average		Number		Weighted-Average
		Outstanding at			Remaining			Exercise		Exercisable		Exercise
		December 28,			Contractual			Price		at December 28,		Price
		2013			Life (years)					2013
	$18.48		262,463			6.9		$	18.48		—	$	—
	$18.49 - 22.81		350,385			4.39		$	21.67		217,170	$	21.62
	$22.82 - 29.07		116,062			2.53		$	25.05		110,062	$	25.05
	$29.08 - 32.09		53,502			0.35		$	32		53,502	$	32
	$32.10 - 32.26		148,623			0.37		$	32.26		148,623	$	32.26
	$32.27 - 48.85		70,250			1.41		$	39.65		70,250	$	39.65
	$48.86 - 50.00		150,000			2.52		$	50		150,000	$	50
	$50.01 - 53.72		141,064			1.2		$	50.87		141,064	$	50.87
	Total		1,292,349			3.38		$	30.43		890,671	$	35.28
	The following table summarizes the status of CRA's non-vested stock options since December 29, 2012:
		Non-vested Options
		Number of			Weighted-Average
		Shares			Fair Value
	Non-vested at December 29, 2012		301,576		$	8.89
Granted		262,463			7.77
Vested		(148,616	)		8.82
Forfeited		(13,745	)		9.7
Non-vested at December 28, 2013		401,678		$	8.16
The total fair value of stock options that vested during fiscal 2013, fiscal 2012, and fiscal 2011 was $1.3 million, $1.5 million, and $1.1 million, respectively. As of December 28, 2013, there was $3.0 million of total unrecognized compensation cost, net of expected forfeitures, related to non-vested stock options granted. That cost is expected to be recognized over a weighted-average period of 2.9 years.
CRA grants restricted stock and time-vesting restricted stock unit awards, which are subject to the execution of a restricted stock agreement or restricted stock unit agreement, as applicable. Generally, shares of restricted stock and time-vesting restricted stock units vest in four equal annual installments beginning on the first anniversary of the date of grant. Total unrecognized compensation cost, net of expected forfeitures, related to restricted stock and time-vesting restricted stock unit awards as of December 28, 2013 was $4.7 million, which is expected to be recognized over a weighted-average period of 2.8 years.
The following table summarizes the status of CRA's non-vested restricted stock and time-vesting restricted stock unit awards since December 29, 2012:
	Non-vested
	Restricted Stock and Stock
	Units
	Number of			Weighted-Average
	Shares			Fair Value
Non-vested at December 29, 2012		299,133		$	22.49
Granted		155,403			18.5
Vested		(134,384	)		22.73
Forfeited		(11,114	)		22.14
Non-vested at December 28, 2013		309,038		$	20.39
As of December 28, 2013, there were 175,277 vested shares outstanding that include a right of first refusal provision in favor of CRA. As of December 28, 2013, there were 236,062 stock options exercisable that include this right of first refusal provision.
Performance share awards are valued based on the fair value of CRA's stock as of the grant date and expense is recognized based on the number of shares expected to vest under the terms of the award under which they are granted. As of December 28, 2013, up to approximately 219,000 shares will become issuable under performance share awards upon achievement of certain financial performance goals, including revenue and profits, for a measurement period falling within the first quarter of fiscal 2014 through the fourth quarter of fiscal 2015.
CRA adopted its 1998 Employee Stock Purchase Plan. The Stock Purchase Plan authorizes the issuance of up to an aggregate of 243,000 shares of common stock to participating employees at a purchase price equal to 85% of fair market value on either the first or the last day of the one-year offering period under the Stock Purchase Plan. In fiscal 2013, fiscal 2012, and fiscal 2011, there were no offering periods under the Stock Purchase Plan and no shares were issued.

Business_Segment_and_Geographi

Business Segment and Geographic Information	12 Months Ended
	Dec. 28, 2013
Business Segment and Geographic Information	'
Business Segment and Geographic Information	'
	13.   Business Segment and Geographic Information
	CRA operates in one business segment, which is consulting services. Revenue and long-lived assets by country, based on the physical location of the operation to which the revenues or the assets relate, are as follows (in thousands):
		Fiscal Year		Fiscal Year		Fiscal Year
		2013		2012		2011
		(52 weeks)		(52 weeks)		(52 weeks)
	Revenue:
	United States	$	216,815	$	207,779	$	224,661
	United Kingdom		46,987		51,059		58,426
	Other		14,630		11,552		22,141
	Total foreign		61,617		62,611		80,567
		$	278,432	$	270,390	$	305,228
		December 28,		December 29,
		2013		2012
	Long-lived assets (property and equipment, net):
	United States	$	13,657	$	15,442
	United Kingdom		1,911		2,452
	Other		87		86
	Total foreign		1,998		2,538
		$	15,655	$	17,980

Income_Taxes

Income Taxes	12 Months Ended
	Dec. 28, 2013
Income Taxes	'
Income Taxes	'
	14.   Income Taxes
	The components of income (loss) before (provision) benefit for income taxes are as follows (in thousands):
		Fiscal Year			Fiscal Year			Fiscal Year
		2013			2012			2011
		(52 weeks)			(52 weeks)			(52 weeks)
	Income (loss) before (provision) benefit for income taxes:
	U.S.	$	13,659		$	(27,290	)	$	26,150
	Foreign		4,259			(30,733	)		1,933
	Total	$	17,918		$	(58,023	)	$	28,083
	The components of income tax provision (benefit) have been recorded in CRA's financial statements as follows (in thousands):
		Fiscal Year			Fiscal Year			Transition
								Period
		2013			2012			2011
		(52 weeks)			(52 weeks)			(52 weeks)
	Income tax provision (benefit)	$	6,683		$	(5,180	)	$	11,138
	Tax deficit on stock option exercises and restricted share vesting charged directly to common stock		254			576			639
		$	6,937		$	(4,604	)	$	11,777
	The provision (benefit) for income taxes consists of the following (in thousands):
		Fiscal Year			Fiscal Year			Fiscal Year
		2013			2012			2011
		(52 weeks)			(52 weeks)			(52 weeks)
	Currently payable:
	Federal	$	1,241		$	3,637		$	15,964
	Foreign		1,264			50			309
	State		254			1,015			3,604
			2,759			4,702			19,877
	Deferred:
	Federal		3,592			(8,163	)		(6,829	)
	Foreign		(238	)		21			(286	)
	State		570			(1,740	)		(1,624	)
		$	3,924		$	(9,882	)	$	(8,739	)
		$	6,683		$	(5,180	)	$	11,138
	A reconciliation of CRA's tax rates with the federal statutory rate is as follows:
		Fiscal Year			Fiscal Year			Fiscal Year
		2013			2012			2011
	Federal statutory rate		35	%		(35.0	)%		35	%
	State income taxes, net of federal income tax benefit		4.4			(1.3	)		7
	Goodwill impairment		—			20.6			—
	Foreign losses benefited		(2.8	)		(0.1	)		(3.0	)
	Losses not benefited		0.3			4.2			—
	Foreign rate differential		(0.4	)		2.1			0.9
	Foreign tax credit		(0.1	)		(0.5	)		(1.4	)
	Uncertain tax positions		(2.1	)		—			—
	Impact of NeuCo's tax provision charges		1.5			0.1			1.2
	Permanently disallowed expenses		1.6			1			1.5
	Other		(0.1	)		—			(1.5	)
			37.3	%		(8.9	)%		39.7	%
	The components of CRA's deferred tax assets (liabilities) are as follows (in thousands):
		December 28,			December 29,
		2013			2012
	Deferred tax assets:
	Accrued compensation and related expense	$	21,064		$	16,743
	Tax basis in excess of financial basis of net accounts receivable		2,363			2,382
	Net operating loss carryforwards		5,421			6,682
	Tax basis in excess of financial basis of fixed assets		1,489			978
	Excess tax over book amortization		—			5,926
	Accrued expenses and other		902			2,565
	Total gross deferred tax assets		31,239			35,276
	Less: valuation allowance		(6,101	)		(7,287	)
	Total deferred tax assets net of valuation allowance		25,138			27,989
	Deferred tax liabilities:
	Tax basis in excess of financial basis of debentures		5,024			6,371
	Excess book over tax amortization		2,938			—
Total deferred tax liabilities		7,962			6,371
Net deferred tax assets	$	17,176		$	21,618
In general, a valuation allowance is recorded against deferred tax assets because CRA's management believes, after considering the available evidence, that it is more likely than not that the assets will not be realized. Reductions in valuation allowances are a result of management's consideration of historical profitability, future expected results and the nature of the related deferred tax assets. The net change in the total valuation allowance for fiscal 2013 was a decrease of approximately $1.2 million compared to fiscal 2012. The $1.2 million decrease was related to the recording of a $1.4 million increase to a deferred tax liability in fiscal 2013 associated with goodwill and a corresponding decrease to valuation allowance and to the utilization of $0.6 million of certain prior net operating losses, offset partially by additional valuation allowances recorded against certain net deferred assets including foreign net operating losses of $0.4 million and NeuCo net operating losses of $0.4 million. The net change in the total valuation allowance for fiscal 2012 was an increase of approximately $2.3 million compared to fiscal 2011. The net change was related to the recording of additional valuation allowances against certain foreign net deferred assets including foreign net operating losses of $2.5 million reduced by the utilization of $0.2 million of certain prior net operating losses. The ultimate realization of deferred tax assets that continue to be subject to valuation allowances is dependent upon the generation of future taxable income during the periods and in the tax jurisdictions in which those temporary differences become deductible.
At December 28, 2013 CRA had $11.8 million of foreign net operating loss carry forwards and $0.4 million in U.S. state net operating loss carryforwards. NeuCo has net operating loss carryforwards for U.S. federal and U.S. state tax purposes of $6.1 million which are subject to a full valuation allowance and begin to expire in 2021. NeuCo files a separate U.S. federal tax return and none of its losses are available to offset CRA's consolidated taxable income. The foreign operating losses have an indefinite life, except for $0.2 million that will begin to expire in 2016.
The aggregate changes in the balances of gross unrecognized tax benefits were as follows (in thousands):
	December 28,			December 29,
	2013			2012
Balance at beginning of period	$	3,032		$	943
Additions for tax positions taken during prior years		372			2,344
Settlements with tax authorities		(3,032	)		(255	)
Balance at end of the period	$	372		$	3,032
CRA files income tax returns in the U.S. federal jurisdiction and various state and foreign jurisdictions. A number of years may elapse before an uncertain tax position, for which CRA has unrecognized tax benefits, is audited and finally resolved. While it is often difficult to predict the final outcome or the timing of resolution of any particular uncertain tax position, CRA believes that its unrecognized tax benefits reflect the most likely outcome. CRA adjusts these unrecognized tax benefits, and the associated interest, in light of changing facts and circumstances. At the end of fiscal 2013, CRA had $67,000 of interest on its unrecognized tax benefit balance. CRA reports accrued interest and penalties related to unrecognized tax benefits in income tax expense. Settlement of any particular position could require the use of cash. Of the total $372,000 balance at the end of fiscal 2013, a favorable resolution would result in $47,000 being recognized as a reduction to the effective income tax rate in the period of resolution. It is reasonably likely that $47,000 of unrecognized tax benefits will reverse within the next twelve months.
The number of years with open tax audits varies depending on the tax jurisdiction. CRA's major taxing jurisdiction is the United States. CRA is no longer subject to U.S. federal examinations by the Internal Revenue Service for years before fiscal 2012. CRA's United Kingdom subsidiary's corporate tax returns are no longer subject to examination by Her Majesty's Revenue and Customs for fiscal years before fiscal 2011. CRA believes its reserves for uncertain tax positions are adequate.
CRA has not provided for deferred income taxes or foreign withholding taxes on undistributed earnings from its foreign subsidiaries of approximately $3.2 million as of December 28, 2013 because such earnings are considered to be indefinitely reinvested. CRA does not rely on these unremitted earnings as a source of funds for its domestic business as it expects to have sufficient cash flow in the U.S. to fund its U.S. operational and strategic needs. If CRA were to repatriate its foreign earnings that are indefinitely reinvested, it would accrue substantially no additional tax expense.

RelatedParty_Transactions

Related-Party Transactions	12 Months Ended
	Dec. 28, 2013
Related-Party Transactions	'
Related-Party Transactions	'
	15.   Related-Party Transactions
	CRA made payments to shareholders of CRA who performed consulting services exclusively for CRA in the amounts of $6.1 million, $5.4 million, and $7.3 million in fiscal 2013, fiscal 2012, and fiscal 2011, respectively. These payments were to exclusive non-employee experts for consulting services performed for CRA's clients in the ordinary course of business.

Restructuring_Charges

Restructuring Charges	12 Months Ended
	Dec. 28, 2013
Restructuring Charges	'
Restructuring Charges	'
	16.   Restructuring Charges
	CRA did not incur any restructuring charges during fiscal 2013.
	During fiscal 2012, CRA incurred pre-tax restructuring expenses of $6.7 million, of which approximately $5.4 million was for termination benefits, facility-related charges, asset write-downs and other charges in connection with the plan committed to by CRA's management during the third quarter of fiscal 2012 to eliminate and restructure selected practice areas and reduce selling, general and administrative costs. In connection with this plan, CRA eliminated its Chemicals practice and closed its Middle East operations. These restructuring actions, along with the repositioning of other select underperforming practice areas, resulted in the reduction of more than 60 consulting positions. Commensurate with these consulting staff reductions, CRA also took significant actions to lower its selling, general and administrative costs by reducing CRA's administrative staff, eliminating excess office space capacity, better rationalizing remaining office space, and lowering administrative spending, particularly related to outside contractors and professional fees. These restructuring actions were designed to intensify the focus of CRA's portfolio, increase the cohesiveness of its services and improve its margins and profitability. The majority of these actions occurred during the third quarter of fiscal 2012, and the remainder was completed during the fourth quarter of fiscal 2012.
	Additionally, during fiscal 2012, CRA entered into an agreement with the landlord of its London, England office to surrender the lease of one of the three floors it leased in the office building in London. Under this agreement, CRA surrendered its lease of this floor on June 30, 2012, instead of on the lease's original termination date of October 2, 2016, and paid the landlord approximately $1.2 million in connection with the surrender. In connection with this surrender, CRA incurred pre-tax restructuring charges of $1.7 million, which included the $1.2 million surrender charge and approximately $0.5 million of fixed asset write-offs and other charges or offsets. During fiscal 2012, CRA also recorded pre-tax restructuring credits of approximately $0.4 million related primarily to adjustments to its leased office space in Houston, TX and Chicago, IL.Of the $6.7 million of restructuring charges recorded during fiscal 2012, approximately $3.8 million was charged to cost of sales, $1.5 million was charged to selling, general and administrative expenses, and $1.4 million was charged to depreciation and amortization expense.
	The restructuring expenses and reserve balance are as follows as of December 28, 2013 and December 29, 2012 (in thousands):
		Office			Employee			Total
		Vacancies			Workforce			Restructuring
					Reduction
	Balance at December 31, 2011	$	3,737		$	—		$	3,737
	Charges incurred during fiscal 2012		2,110			4,618			6,728
	Amounts paid, net of amounts received, during fiscal 2012		(3,514	)		(3,718	)		(7,232	)
	Non-cash adjustments and effect of foreign currency translation during fiscal 2012		(227	)		(27	)		(254	)
	Balance at December 29, 2012	$	2,106		$	873		$	2,979
	Charges incurred during fiscal 2013		—			—			—
	Amounts paid, net of amounts received, during fiscal 2013		(759	)		(729	)		(1,488	)
	Non-cash adjustments and effect of foreign currency translation during fiscal 2013		(177	)		(144	)		(321	)
	Balance at December 28, 2013	$	1,170		$	—		$	1,170
	The $1.2 million restructuring liability as of December 28, 2013 is expected to be paid during the period from fiscal 2014 through the third quarter of fiscal 2015.
	On the accompanying balance sheet as of December 28, 2013, the reserve balance of $1.2 million was classified as follows: $0.8 million in "current portion of deferred rent" and $0.4 million in "deferred rent and other non-current liabilities".

Quarterly_Financial_Data_Unaud

Quarterly Financial Data (Unaudited)	12 Months Ended
	Dec. 28, 2013
Quarterly Financial Data (Unaudited)	'
Quarterly Financial Data (Unaudited)	'
	17.   Quarterly Financial Data (Unaudited)
		Quarter Ended
		March 30,		June 29,			September 28,			December 28,
		2013		2013			2013			2013
		(In thousands, except per share data)
	Revenues	$	63,130	$	65,203		$	74,427		$	75,672
	Gross profit		21,115		20,161			23,850			24,044
	Income from operations		3,774		3,170			6,114			5,459
	Income before provision for income taxes		3,377		3,368			5,952			5,221
	Net income		2,835		1,351			3,333			3,716
	Net (income) loss attributable to noncontrolling interest, net of tax		134		58			(63	)		6
	Net income attributable to CRA International, Inc.		2,969		1,409			3,270			3,722
	Basic net income per share	$	0.3	$	0.14		$	0.32		$	0.37
	Diluted net income per share	$	0.29	$	0.14		$	0.32		$	0.37
	Weighted average number of shares outstanding:
	Basic		9,994		10,100			10,093			10,071
	Diluted		10,084		10,188			10,192			10,148
		Quarter Ended
		March 31,		June 30,			September 29,			December 29,
		2012		2012			2012			2012
		(In thousands, except per share data)
	Revenues	$	69,132	$	67,813		$	65,912		$	67,533
	Gross profit		22,645		22,365			19,737			23,262
	Income (loss) from operations		3,306		2,808			1,035			(64,959	)
	Income (loss) before (provision) benefit for income taxes		3,253		2,695			1,016			(64,987	)
	Net income (loss)		436		773			(706	)		(53,346	)
	Net (income) loss attributable to noncontrolling interest, net of tax		83		(54	)		(38	)		(138	)
	Net income (loss) attributable to CRA International, Inc.		519		719			(744	)		(53,484	)
	Basic net income (loss) per share	$	0.05	$	0.07		$	(0.07	)	$	(5.33	)
	Diluted net income (loss) per share	$	0.05	$	0.07		$	(0.07	)	$	(5.33	)
	Weighted average number of shares outstanding:
	Basic		10,316		10,242			10,084			10,027
	Diluted		10,493		10,381			10,084			10,027
	Earnings per share is calculated for each period, and the sum of the four quarters may not equal the full year amount.

Compensation_Arrangements

Compensation Arrangements	12 Months Ended
	Dec. 28, 2013
Compensation Arrangements	'
Compensation Arrangements	'
	18.   Compensation Arrangements
	In connection with an acquisition completed in fiscal 2013, CRA agreed to pay incentive performance awards to certain non-employee experts and employees of the acquired business, if specific performance targets are met from June 2013 through May 2017. Retention of amounts paid is contingent on their continued relationships with CRA through May 2019. The amount of the award could fluctuate depending on future performance through May 2017. Changes in the estimated award are expensed prospectively over the remaining service period.

Subsequent_Event

Subsequent Event	12 Months Ended
	Dec. 28, 2013
Subsequent Event	'
Subsequent Event	'
	19.   Subsequent Event
	On February 24, 2014, CRA entered into a new lease with BP Hancock LLC, as landlord, for the 9th and 10th floors (a total of 57,602 square feet) of the same office building at 200 Clarendon Street, Boston, Massachusetts in which CRA's Boston offices are currently located. The lease's base term will expire ten years from the date that CRA begins paying fixed rent under the lease and, subject to certain conditions, will be extendible by CRA for two five-year periods. The annual fixed rent for this office space (which does not include customary operating costs and expenses) will be $42 per square foot, or $2.4 million, for the first year of the lease's base term and will increase at the rate of $1.00 per square foot during the remainder of the lease's base term. The lease gives CRA a right of first refusal to rent certain additional office space in the office building if it becomes available. The performance of our obligations under the lease is secured by a $1 million letter of credit.
	Concurrently with our entering into this new lease, CRA also entered into an amendment of its existing lease with BP Hancock LLC, as landlord, for the office space it currently rents in the office building described above, which currently expires on March 31, 2015. Except with respect to 25,099 square feet of office space covered by this lease, the amendment either extends the term of this lease to, or if prior to March 31, 2015 terminates this lease on, the day prior to the date that CRA begins paying fixed rent under the new lease described above. If the term of the existing lease is extended, the amendment provides that the base rent payable under this lease during the extension period will be $2.4 million per year.
	CRA currently expects that the term of the new lease will commence, and the relocation of its Boston offices to the 9th and 10th floors of the office building at 200 Clarendon Street, Boston, Massachusetts will occur, sometime in the second quarter of fiscal 2015.

Summary_of_Significant_Account1

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 28, 2013
Summary of Significant Accounting Policies	'
Fiscal Year	'
	Fiscal Year
	CRA's fiscal year end is the Saturday nearest December 31 of each year. CRA's fiscal years periodically contain 53 weeks rather than 52 weeks. Fiscal 2013, fiscal 2012, and fiscal 2011 were 52-week years.
Principles of Consolidation	'
	Principles of Consolidation
	The consolidated financial statements include the accounts of CRA and its wholly owned subsidiaries. In addition, as more fully explained below, the consolidated financial statements include CRA's interest in NeuCo, Inc. ("NeuCo"). All significant intercompany accounts have been eliminated.
NeuCo Interest	'
	NeuCo Interest
	CRA's ownership interest in NeuCo is 55.89%. CRA's ownership interest has constituted control under GAAP for all periods presented. Therefore, NeuCo's financial results have been consolidated with CRA's and the portion of NeuCo's results allocable to its other owners is shown as "noncontrolling interest." NeuCo's revenues included in the CRA's consolidated statements of operations for fiscal 2013, fiscal 2012, and fiscal 2011 totaled approximately $5.1 million, $5.5 million, and $6.2 million, respectively. NeuCo's net loss included in CRA's consolidated statements of operations for fiscal 2013 was approximately $0.3 million. NeuCo's net income included in CRA's consolidated statements of operations for fiscal 2012 and fiscal 2011 was approximately $0.3 million and $0.2 million, respectively. NeuCo's net loss, net of amounts allocable to its other owners, included in CRA's consolidated statements of operations for fiscal 2013 was approximately $0.2 million. NeuCo's net income, net of amounts allocable to its other owners, included in CRA's consolidated statements of operations for fiscal 2012 and fiscal 2011 was approximately $0.2 million and $0.1 million, respectively. NeuCo's interim reporting schedule is based on calendar month-ends, and its fiscal year end is the last Saturday of November. CRA's quarterly results could include a few days reporting lag between CRA's quarter end and the most recent financial statements available from NeuCo. CRA does not believe that the reporting lag, if any, will have a significant impact on CRA's consolidated statements of operations or financial condition.
Estimates	'
	Estimates
	The preparation of financial statements in conformity with accounting principles generally accepted in the U.S. requires management to make significant estimates and judgments that affect the reported amounts of assets and liabilities, and disclosure of contingent assets and liabilities, at the date of the financial statements, and the reported amounts of consolidated revenues and expenses during the reporting period. Estimates in these consolidated financial statements include, but are not limited to, accounts and unbilled receivable allowances, revenue recognition on fixed price contracts, depreciation of property and equipment, share-based compensation, valuation of acquired intangible assets, impairment of long lived assets and goodwill, accrued and deferred income taxes, valuation allowances on deferred tax assets, accrued compensation, accrued exit costs, and other accrued expenses. These items are monitored and analyzed by CRA for changes in facts and circumstances, and material changes in these estimates could occur in the future. Changes in estimates are recorded in the period in which they become known. CRA bases its estimates on historical experience and various other assumptions that CRA believes to be reasonable under the circumstances. Actual results may differ from those estimates if CRA's assumptions based on past experience or other assumptions do not turn out to be substantially accurate.
Revenue Recognition	'
	Revenue Recognition
	CRA derives substantially all of its revenues from the performance of professional services. The contracts that CRA enters into and operates under specify whether the engagement will be billed on a time-and-materials or a fixed-price basis. These engagements generally last three to six months, although some of CRA's engagements can be much longer in duration. Each contract must be approved by one of CRA's vice presidents.
	CRA recognizes substantially all of its revenues under written service contracts with its clients when the fee is fixed or determinable, as the services are provided, and only in those situations where collection from the client is reasonably assured and sufficient contractual documentation has been obtained. In certain cases CRA provides services to its clients without sufficient contractual documentation, or fees are tied to performance-based criteria, which require CRA to defer revenue in accordance with U.S. GAAP. In these cases, these amounts are fully reserved until all criteria for recognizing revenue are met.
	CRA's revenues include projects secured by our non-employee experts as well as projects secured by our employees. CRA recognizes all project revenue on a gross basis based on the consideration of the criteria set forth in Accounting Standards Codification ("ASC") Topic 605-45, Principal Agent Considerations.
	Most of CRA's revenue is derived from time-and-materials service contracts. Revenues from time-and-materials service contracts are recognized as services are provided based upon hours worked and contractually agreed-upon hourly rates, as well as indirect fees based upon hours worked.
	Revenues from the majority of CRA's fixed-price engagements are recognized on a proportional performance method based on the ratio of costs incurred, substantially all of which are labor-related, to the total estimated project costs. CRA derived approximately 13%, 15%, and 22% of consolidated revenues from fixed-price engagements in fiscal 2013, fiscal 2012, and fiscal 2011, respectively. In general, project costs are classified as costs of services and are based on the direct salary of the consultants on the engagement plus all direct expenses incurred to complete the engagement, including any amounts billed to us by our non-employee experts. The proportional performance method is used because reasonably dependable estimates of the revenues and costs applicable to various stages of a contract can be made, based on historical experience and the terms set forth in the contract, and are indicative of the level of benefit provided to CRA's clients. Fixed-price contracts generally convert to time-and-materials contracts in the event the contract terminates. CRA's management maintains contact with project managers to discuss the status of the projects and, for fixed-price engagements, management is updated on the budgeted costs and resources required to complete the project. These budgets are then used to calculate revenue recognition and to estimate the anticipated income or loss on the project. Occasionally, CRA has been required to commit unanticipated additional resources to complete projects, which has resulted in lower than anticipated income or losses on those contracts. CRA may experience similar situations in the future. Provisions for estimated losses on contracts are made during the period in which such losses become probable and can be reasonably estimated. To date, such losses have not been significant.
	Revenues also include reimbursable expenses, which include travel and other out-of-pocket expenses, outside consultants, and other reimbursable expenses. Reimbursable expenses are as follows (in thousands):
		Year Ended			Year Ended			Year Ended
		December 28,			December 29,			December 31,
		2013			2012			2011
		(52 weeks)			(52 weeks)			(52 weeks)
	Reimbursable expenses	$	37,320		$	33,530		$	39,722
	CRA maintains accounts receivable allowances for estimated losses and disputed amounts resulting from clients' failure to make required payments. CRA bases its estimates on historical collection experience, current trends, and credit policy. In determining these estimates, CRA examines historical write-offs of its receivables and reviews client accounts to identify any specific customer collection issues. If the financial condition of CRA's customers were to deteriorate or disputes were to arise regarding the services provided, resulting in an impairment of their ability or intent to make payment, additional allowances may be required.
	Unbilled services represent revenue recognized by CRA for services performed but not yet billed to the client. Deferred revenue represents amounts billed or collected in advance of services rendered.
	CRA collects goods and services and value added taxes from customers and records these amounts on a net basis, which is within the scope of ASC Topic 605-45, Principal Agent Considerations.
Cash Equivalents	'
	Cash Equivalents
	Cash equivalents consist principally of money market funds and commercial paper with maturities of three months or less when purchased. As of December 28, 2013, a substantial portion of CRA's cash accounts was concentrated at a single financial institution, which potentially exposes CRA to credit risks. The financial institution has a short-term credit rating of A-2 by Standard & Poor's ratings services. CRA has not experienced any losses related to such accounts. CRA does not believe that there is significant risk of non-performance by the financial institution and the cash on deposit is fully liquid. CRA continually monitors the credit ratings of the institution.
	The carrying amounts of these instruments classified as cash equivalents are stated at amortized cost, which approximates fair value because of their short-term maturity.
Fair Value of Financial Instruments	'
	Fair Value of Financial Instruments
	CRA's financial instruments, including cash, cash equivalents, accounts receivable, loans and advances from employees and non-employee experts, accounts payable, and accrued expenses, are carried at cost, which approximates their fair value because of the short-term maturity of these instruments or because their stated interest rates are indicative of market interest rates.
Goodwill	'
	Goodwill
	In accordance with ASC Topic 350, "Intangibles—Goodwill and Other", goodwill is not subject to amortization, but is monitored at least annually for impairment, or more frequently, as necessary, if events or circumstances exist that would more likely than not reduce the fair value of the reporting unit below its carrying amount. For the CRA's goodwill impairment analysis, CRA operates under one reporting unit. Under ASC Topic 350, in performing the first step of the goodwill impairment testing and measurement process, CRA compares its entity-wide estimated fair value to net book value to identify potential impairment. Management estimates the entity-wide fair value utilizing CRA's market capitalization, plus an appropriate control premium. Market capitalization is determined by multiplying the shares outstanding on the test date by the market price of CRA's common stock on that date. CRA has utilized a control premium which considers appropriate industry, market and other pertinent factors, including indications of such premiums from data on recent acquisition transactions. If the fair value of CRA is less than its net book value, the second step is performed to determine if goodwill is impaired. If CRA determines through the impairment evaluation process that goodwill has been impaired, an impairment charge would be recorded in the consolidated statement of operations.
	There were no impairment losses related to goodwill during fiscal 2013 as there were no events or circumstances that would more likely than not reduce CRA's fair value below its carrying amount.
	When CRA performed its annual impairment test in the fourth quarter of fiscal 2012, its net book value exceeded its market capitalization plus an estimated control premium. Therefore, CRA was required to perform the second step of the goodwill impairment test. In this step, CRA's fair value is allocated among all of its assets and liabilities, including any unrecognized intangible assets, in a hypothetical analysis that calculates the implied fair value of goodwill in the same manner as if CRA were being acquired in a business acquisition. If the implied fair value of goodwill is less than the recorded goodwill, an impairment charge is recorded for the difference. During the process of conducting the second step of the annual goodwill impairment test in the fourth quarter of fiscal 2012, CRA identified significant unrecognized intangible assets. The combination of these hypothetical unrecognized intangible assets and other hypothetical unrecognized fair value changes to the carrying values of other assets and liabilities, together with the lower fair value calculated in the first step of the annual impairment test, resulted in a goodwill impairment charge of $71.4 million in the fourth quarter of fiscal 2012.
	The re-measurement of goodwill is classified as a Level 3 fair value assessment due to the significance of unobservable inputs developed using CRA-specific information. CRA used a combination of the income, cost and market approach techniques to determine the fair value of its assets and liabilities. The fair value adjustment to goodwill was computed as the difference between CRA's fair value and the fair value of underlying assets and liabilities. The unobservable inputs used to determine the fair value of the underlying assets and liabilities were based on CRA-specific information such as estimates of revenue and cost growth rates, profit margins, discount rates, and cost estimates.
Intangible Assets	'
	Intangible Assets
	Intangible assets that are separable from goodwill and have determinable useful lives are valued separately and amortized over their estimated useful lives. Intangible assets consist of non-competition agreements, customer relationships, customer lists, developed technology, and trademarks, all of which are generally amortized on a straight-line basis over their remaining useful lives of four to ten years.
Property and Equipment	'
	Property and Equipment
	Property and equipment are recorded at cost. Depreciation is calculated using the straight-line method based on the estimated useful lives of three years for computer equipment, three to ten years for computer software, and ten years for furniture and fixtures. Amortization of leasehold improvements is calculated using the straight-line method over the shorter of the lease term or the estimated useful life of the leasehold improvements. Expenditures for maintenance and repairs are expensed as incurred. Expenditures for renewals and betterments are capitalized.
Leases and Deferred Rent	'
	Leases and Deferred Rent
	CRA leases all of its office space. Leases are evaluated and classified as operating or capital leases for financial reporting purposes. For leases that contain rent escalations and rent holidays, CRA records the total rent payable during the lease term, as determined above, on a straight-line basis over the term of the lease and records the difference between the rents paid and the straight-line rent as deferred rent. Additionally, any tenant improvement allowances received from the lessor are recorded as a reduction to deferred rent.
Impairment of Long-Lived Assets	'
	Impairment of Long-Lived Assets
	CRA reviews the carrying value of its long-lived assets (primarily property and equipment and intangible assets) to assess the recoverability of these assets whenever events or circumstances indicate that impairment may have occurred. Factors CRA considers important that could trigger an impairment review include the following:
	•
	a significant underperformance relative to expected historical or projected future operating results;
	•
	a significant change in the manner of CRA's use of the acquired asset or the strategy for CRA's overall business; and
	•
	a significant negative industry or economic trend.
	If CRA determines that an impairment review is required, CRA would review the expected future undiscounted cash flows to be generated by the assets or asset groups. If CRA determines that the carrying value of long-lived assets or asset groups may not be recoverable, CRA would measure any impairment based on a projected discounted cash flow method using a discount rate determined by CRA to be commensurate with the risk inherent in CRA's current business model. If impairment is indicated through this review, the carrying amount of the assets would be reduced to their estimated fair value.
Concentration of Credit Risk	'
	Concentration of Credit Risk
	CRA's billed and unbilled receivables consist of receivables from a broad range of clients in a variety of industries located throughout the U.S. and in other countries. CRA performs a credit evaluation of its clients to minimize its collectability risk. Periodically, CRA will require advance payment from certain clients. However, CRA does not require collateral or other security. CRA maintains accounts receivable allowances for estimated losses and disputed amounts resulting from clients' failures to make required payments. CRA bases its estimates on historical collection experience, current trends, and credit policy. In determining these estimates, CRA examines historical write-offs of its receivables and reviews client accounts to identify any specific customer collection issues. If the financial condition of any of CRA's customers were to deteriorate, resulting in an impairment of their ability or intent to make payment, additional allowances may be required.
	A rollforward of the accounts receivable allowances is as follows (in thousands):
		Fiscal			Fiscal
		Year			Year
		2013			2012
	Balance at beginning of period	$	9,459		$	6,548
	Change related to NeuCo		(2	)		—
	Additions charged to revenues		5,644			6,808
	Amounts written off		(7,891	)		(3,897	)
	Balance at end of period	$	7,210		$	9,459
	Amounts deemed uncollectible are recorded as a reduction to revenues.
Share-Based Compensation	'
	Share-Based Compensation
	CRA accounts for equity-based compensation using a fair value based recognition method. Under the fair value recognition requirements of ASC Topic 718, "Compensation-Stock Compensation" ("ASC Topic 718"), share-based compensation cost is estimated at the grant date based on the fair value of the award and is recognized as expense over the requisite service period of the award. The amount of share-based compensation expense recognized at any date must at least equal the portion of grant date value of the award that is vested at that date.
	For share-based awards granted to non-employee experts, CRA accounts for the compensation under variable accounting in accordance with ASC Topic 718 and ASC Topic 505-50, "Equity-Based Payments to Non-Employees" (formerly Emerging Issues Task Force 96-18, "Accounting for Equity Instruments That Are Issued to Other Than Employees for Acquiring, or in Conjunction with Selling, Goods or Services"), and recognizes the cost over the related vesting period. For performance-vesting restricted stock units awarded to employees, CRA accounts for the compensation under variable accounting in accordance with ASC Topic 718, and recognizes the cost over the related vesting period.
Income Taxes	'
	Income Taxes
	CRA accounts for income taxes using the asset and liability method of accounting for income taxes. Deferred tax assets and liabilities are recognized based upon anticipated future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective income tax bases, and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. A valuation allowance is recorded to reduce the carrying amounts of deferred tax assets if it is more likely than not that such assets will not be realized.
	In addition, the calculation of CRA's tax liabilities involves dealing with uncertainties in the application of complex tax regulations in several different tax jurisdictions. CRA records liabilities for estimated tax obligations resulting in a provision for taxes that may become payable in the future, in accordance with ASC Topic 740-10, "Income Taxes," which prescribes a recognition threshold and measurement attribute for the financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return and also provides guidance on derecognition, classification, interest and penalties, accounting in interim periods, and disclosure. CRA includes accrued interest and penalties, if any, related to uncertain tax positions in income tax expense.
Foreign Currency Translation	'
	Foreign Currency Translation
	Balance sheet accounts of CRA's foreign subsidiaries are translated into U.S. dollars at year-end exchange rates and operating accounts are translated at average exchange rates for each year. The resulting translation adjustments are recorded in shareholders' equity as a component of accumulated other comprehensive income (loss). Foreign currency transactions are translated at current exchanges rates, with adjustments recorded in the statement of operations. The effect of transaction gains and losses recorded in income (loss) before (provision) benefit for income taxes amounted to losses of $0.2 million, $0.2 million, and $0.4 million for fiscal 2013, fiscal 2012, and fiscal 2011, respectively.
Recent Accounting Standards	'
	Recent Accounting Standards
	Presentation of Unrecognized Tax Benefits
	In July 2013, the Financial Accounting Standards Board (the "FASB") issued Accounting Standards Update ("ASU") No. 2013-11, Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists ("ASU 2013-11") to clarify the presentation of current and deferred income taxes on the balance sheet. Under ASU 2013-11, companies generally must present an unrecognized tax benefit, or a portion of an unrecognized tax benefit, for an NOL carryforward, similar tax loss, or tax credit carryforward using the "net presentation" approach as a reduction of a deferred tax asset, with some allowed exceptions. ASU 2013-11 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2013. Early adoption is permitted and entities may choose to apply the amendments retrospectively to each prior reporting period presented. CRA believes the adoption of ASU 2013-11 will have no impact on its financial position, results of operations, cash flows, or disclosures.
	Comprehensive Income
	In February 2013, the FASB issued ASU No. 2013-02, Comprehensive Income (Topic 220): Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income ("ASU 2013-02"). ASU 2013-02 requires an entity disclose in a single location (either on the face of the financial statement that reports net income or in the notes) the effects of reclassifications out of accumulated other comprehensive income. For items reclassified out of accumulated other comprehensive income and into net income in their entirety, entities must disclose the effect of the reclassification on each affected net income item. For accumulated other comprehensive income reclassification items that are not reclassified in their entirety into net income, entities must provide a cross reference to other required U.S. GAAP disclosures. There is no change in the requirement to present the components of net income and other comprehensive income in either a single continuous statement or two separate consecutive statements. ASU 2013-02 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2012 and should be applied prospectively. CRA's adoption of ASU 2013-02 in the first quarter of fiscal 2013 had no impact on its financial position, results of operations, cash flows, or disclosures.
	Cumulative Translation Adjustment
	In March 2013, the FASB issued ASU No. 2013-05, Parent's Accounting for the Cumulative Translation Adjustment upon Derecognition of Certain Subsidiaries or Groups of Assets within a Foreign Entity or of an Investment in a Foreign Entity ("ASU 2013-05"). ASU 2013-05 addresses the accounting for the cumulative translation adjustment when a parent either sells a part or all of its investment in a foreign entity or no longer holds a controlling financial interest in a subsidiary or group of assets that is a nonprofit activity or a business within a foreign entity. ASU 2013-05 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2013 and should be applied prospectively. Early adoption is permitted. CRA believes the adoption of ASU 2013-05 will have no impact on its financial position, results of operations, cash flows, or disclosures.
	Intangibles
	In July 2012, the FASB issued ASU No. 2012-02, Intangibles—Goodwill and Other (Topic 350): Testing Indefinite-Lived Intangible Assets for Impairment ("ASU 2012-02") to simplify the guidance for testing the decline in the realizable value (impairment) of indefinite-lived intangible assets other than goodwill. Under former guidance, an organization was required to test an indefinite-lived intangible asset for impairment on at least an annual basis by comparing the fair value of the asset with its carrying amount. If the carrying amount of an indefinite-lived intangible asset exceeded its fair value, an impairment loss was recognized in an amount equal to the difference. ASU 2012-02 allows an organization the option to first assess qualitative factors to determine whether it is necessary to perform the quantitative impairment test. An organization electing to perform a qualitative assessment is no longer required to calculate the fair value of an indefinite-lived intangible asset unless the organization determines, based on a qualitative assessment, that it is "more likely than not" that the asset is impaired. ASU 2012-02 was effective for annual and interim impairment tests performed for fiscal years beginning after September 15, 2012. CRA's adoption of ASU 2012-02 in fiscal 2013 had no impact on its financial position, results of operations, cash flows, or disclosures.

Summary_of_Significant_Account2

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 28, 2013
Summary of Significant Accounting Policies	'
Schedule of reimbursable expenses included in revenues	'
	Reimbursable expenses are as follows (in thousands):
		Year Ended			Year Ended			Year Ended
		December 28,			December 29,			December 31,
		2013			2012			2011
		(52 weeks)			(52 weeks)			(52 weeks)
	Reimbursable expenses	$	37,320		$	33,530		$	39,722
Schedule of Roll forward of the accounts receivable allowances	'
	A rollforward of the accounts receivable allowances is as follows (in thousands):
		Fiscal			Fiscal
		Year			Year
		2013			2012
	Balance at beginning of period	$	9,459		$	6,548
	Change related to NeuCo		(2	)		—
	Additions charged to revenues		5,644			6,808
	Amounts written off		(7,891	)		(3,897	)
	Balance at end of period	$	7,210		$	9,459

Prepaid_Expenses_and_Other_Cur1

Prepaid Expenses and Other Current Assets, and Other Assets (Tables)	12 Months Ended
	Dec. 28, 2013
Prepaid Expenses and Other Current Assets, and Other Assets	'
Schedule of prepaid expenses and other current assets	'
	Prepaid expenses and other current assets consist of the following (in thousands):
		December 28,		December 29,
		2013		2012
	Term loans to employees and non-employee experts	$	1,764	$	8,614
	Other		10,011		14,387
	Total	$	11,775	$	23,001
Schedule of other assets	'
	Other assets consist of the following (in thousands):
		December 28,		December 29,
		2013		2012
	Forgivable loans to employees and non-employee experts	$	51,083	$	15,448
	Other		3,538		6,223
	Total	$	54,621	$	21,671

Goodwill_and_Intangible_Assets1

Goodwill and Intangible Assets (Tables)	12 Months Ended
	Dec. 28, 2013
Goodwill and Intangible Assets	'
Schedule of changes in the carrying amount of goodwill	'
	The changes in the carrying amount of goodwill for fiscal 2013 and fiscal 2012 are as follows (in thousands):
		Goodwill,			Accumulated			Goodwill,
		gross			impairment			net
					losses
	Balance at December 29, 2012	$	142,658		$	(71,893	)	$	70,765
	Goodwill adjustments related to acquisitions		10,563			—			10,563
	Goodwill adjustments related to NeuCo		(63	)		—			(63	)
	Effect of foreign currency translation		308			—			308
	Balance at December 28, 2013	$	153,466		$	(71,893	)	$	81,573
		Goodwill,			Accumulated			Goodwill,
		gross			impairment			net
					losses
	Balance at December 31, 2011	$	141,153		$	(499	)	$	140,654
	Goodwill impairment		—			(71,394	)		(71,394	)
	Goodwill adjustments related to sale of practice		(29	)		—			(29	)
	Effect of foreign currency translation		1,534			—			1,534
	Balance at December 29, 2012	$	142,658		$	(71,893	)	$	70,765
Schedule of components of acquired identifiable intangible assets	'
	The components of acquired identifiable intangible assets are as follows (in thousands):
		December 28,			December 29,
		2013			2012
	Non-competition agreements, net of accumulated amortization of $3,802, and $3,311, respectively	$	598		$	1,047
	Customer relationships, net of accumulated amortization of $3,550 and $2,840, respectively		3,909			691
	Other intangible assets, net of accumulated amortization of $1,040, and $971, respectively		30			96
		$	4,537		$	1,834
Schedule of expected amortization of intangible assets	'
	Amortization of intangible assets held at December 28, 2013 for the next five fiscal years is expected to be as follows (in thousands):
	Fiscal Year	Amortization
		Expense
	2014	$	1,111
	2015		768
	2016		579
	2017		537
	2018		512
		$	3,507

Property_and_Equipment_Tables

Property and Equipment (Tables)	12 Months Ended
	Dec. 28, 2013
Property and Equipment	'
Schedule of property and equipment	'
	Property and equipment consist of the following (in thousands):
		December 28,			December 29,
		2013			2012
	Computer, office equipment and software	$	25,034		$	24,867
	Leasehold improvements		21,388			20,622
	Furniture		7,788			7,886
			54,210			53,375
	Accumulated depreciation and amortization		(38,555	)		(35,395	)
		$	15,655		$	17,980

Accrued_Expenses_Tables

Accrued Expenses (Tables)	12 Months Ended
	Dec. 28, 2013
Accrued Expenses	'
Schedule of accrued expenses	'
	Accrued expenses consist of the following (in thousands):
		December 28,		December 29,
		2013		2012
	Compensation and related expenses	$	51,960	$	40,329
	Income taxes payable		3,503		626
	Other		10,194		4,350
		$	65,657	$	45,305

Leases_Tables

Leases (Tables)	12 Months Ended
	Dec. 28, 2013
Leases	'
Schedule of minimum rental commitments for office space and equipment leases	'
	At December 28, 2013, CRA had the following minimum rental commitments for office space and equipment leases, all of which are under non-cancelable operating leases (in thousands):
	Fiscal Year	Rental
		Commitments
	2014	$	13,912
	2015		8,824
	2016		4,038
	2017		1,908
	2018		850
	Thereafter		17
		$	29,549
	Future minimum rentals under sublease arrangements		(2,918	)
		$	26,631

Net_Income_Loss_Per_Share_Tabl

Net Income (Loss) Per Share (Tables)	12 Months Ended
	Dec. 28, 2013
Net Income (Loss) Per Share	'
Schedule of reconciliation of basic to diluted weighted average shares of common stock outstanding	'
	A reconciliation of basic to diluted weighted average shares of common stock outstanding is as follows (in thousands):
		Fiscal Year		Fiscal Year		Fiscal Year
		2013		2012		2011
	Basic weighted average shares outstanding		10,084		10,167		10,555
	Common stock equivalents:
	Stock options and restricted stock		89		—		184
	Diluted weighted average shares outstanding		10,173		10,167		10,739

ShareBased_Compensation_Tables

Share-Based Compensation (Tables)	12 Months Ended
	Dec. 28, 2013
Share-Based Compensation	'
Schedule of weighted average assumptions used to estimate the fair market value of the stock options at the date of grant	'
		2013			2011
	Risk-free interest rate		1.4	%		1	%
	Expected volatility		47	%		54	%
	Weighted average expected life (in years)		5			5
	Expected dividends		—			—
Schedule of rollforward of the maximum number of shares issuable under the 2006 Incentive Plan	'
	The following is a rollforward of the maximum number of shares issuable under the 2006 Incentive Plan as of December 28, 2013:
		Actual			Shares Using
		Shares			Fungibility Ratio
	Maximum shares of common stock issuable under the 2006 Incentive Plan					4,874,000
	Restricted shares or units granted/reserved through March 12, 2008		471,827			(849,289	)
	Restricted shares or units granted/reserved from March 12, 2008 to April 29, 2010		352,932			(776,450	)
	Restricted shares or units granted/reserved on or after April 30, 2010		1,196,776			(2,190,100	)
	Cancellation of restricted shares or units through March 12, 2008		91,277			164,299
	Cancellation of restricted shares or units from March 12, 2008 to April 29, 2010		91,964			202,321
	Cancellation of restricted shares or units on or after April 30, 2010		302,374			553,345
	Options granted					(916,118	)
	Options cancelled					183,208
	Options forfeited					10,000
	Shares available for grant under the 2006 Incentive Plan					1,255,216
Summary of option activity	'
		Options			Weighted			Weighted Average		Aggregate
					Average			Remaining		Intrinsic
					Exercise			Contractual		Value
					Price			Term
										(in thousands)
	Outstanding at December 29, 2012		1,169,478		$	32.33
	Fiscal 2013:
	Granted		262,463			18.48
	Exercised		(13,389	)		15.44
	Forfeited		(126,203	)		24.84
	Outstanding at December 28, 2013		1,292,349			30.43			3.38	$	585
	Options exercisable at December 28, 2013		890,671		$	35.28			2.15	$	—
Summary of options outstanding and options exercisable	'
	The following table summarizes stock options outstanding and stock options exercisable as of December 28, 2013:
		Options Outstanding								Options Exercisable
	Range of Exercise Prices	Number			Weighted-Average			Weighted-Average		Number		Weighted-Average
		Outstanding at			Remaining			Exercise		Exercisable		Exercise
		December 28,			Contractual			Price		at December 28,		Price
		2013			Life (years)					2013
	$18.48		262,463			6.9		$	18.48		—	$	—
	$18.49 - 22.81		350,385			4.39		$	21.67		217,170	$	21.62
	$22.82 - 29.07		116,062			2.53		$	25.05		110,062	$	25.05
	$29.08 - 32.09		53,502			0.35		$	32		53,502	$	32
	$32.10 - 32.26		148,623			0.37		$	32.26		148,623	$	32.26
	$32.27 - 48.85		70,250			1.41		$	39.65		70,250	$	39.65
	$48.86 - 50.00		150,000			2.52		$	50		150,000	$	50
	$50.01 - 53.72		141,064			1.2		$	50.87		141,064	$	50.87
	Total		1,292,349			3.38		$	30.43		890,671	$	35.28
Summary of non-vested stock options	'
	The following table summarizes the status of CRA's non-vested stock options since December 29, 2012:
		Non-vested Options
		Number of			Weighted-Average
		Shares			Fair Value
	Non-vested at December 29, 2012		301,576		$	8.89
	Granted		262,463			7.77
	Vested		(148,616	)		8.82
	Forfeited		(13,745	)		9.7
	Non-vested at December 28, 2013		401,678		$	8.16
Summary of non-vested restricted stock and time-vesting restricted stock unit awards	'
	The following table summarizes the status of CRA's non-vested restricted stock and time-vesting restricted stock unit awards since December 29, 2012:
		Non-vested
		Restricted Stock and Stock
		Units
		Number of			Weighted-Average
		Shares			Fair Value
	Non-vested at December 29, 2012		299,133		$	22.49
	Granted		155,403			18.5
	Vested		(134,384	)		22.73
	Forfeited		(11,114	)		22.14
	Non-vested at December 28, 2013		309,038		$	20.39

Business_Segment_and_Geographi1

Business Segment and Geographic Information (Tables)	12 Months Ended
	Dec. 28, 2013
Business Segment and Geographic Information	'
Schedule of revenue by country, based on the physical location of the operation to which the revenues relate	'
	Revenue and long-lived assets by country, based on the physical location of the operation to which the revenues or the assets relate, are as follows (in thousands):
		Fiscal Year		Fiscal Year		Fiscal Year
		2013		2012		2011
		(52 weeks)		(52 weeks)		(52 weeks)
	Revenue:
	United States	$	216,815	$	207,779	$	224,661
	United Kingdom		46,987		51,059		58,426
	Other		14,630		11,552		22,141
	Total foreign		61,617		62,611		80,567
		$	278,432	$	270,390	$	305,228
		December 28,		December 29,
		2013		2012
	Long-lived assets (property and equipment, net):
	United States	$	13,657	$	15,442
	United Kingdom		1,911		2,452
	Other		87		86
	Total foreign		1,998		2,538
		$	15,655	$	17,980

Income_Taxes_Tables

Income Taxes (Tables)	12 Months Ended
	Dec. 28, 2013
Income Taxes	'
Schedule of components of income (loss) before (provision) benefit for income taxes	'
	The components of income (loss) before (provision) benefit for income taxes are as follows (in thousands):
		Fiscal Year			Fiscal Year			Fiscal Year
		2013			2012			2011
		(52 weeks)			(52 weeks)			(52 weeks)
	Income (loss) before (provision) benefit for income taxes:
	U.S.	$	13,659		$	(27,290	)	$	26,150
	Foreign		4,259			(30,733	)		1,933
	Total	$	17,918		$	(58,023	)	$	28,083
Schedule of components of income tax provision (benefit)	'
	The components of income tax provision (benefit) have been recorded in CRA's financial statements as follows (in thousands):
		Fiscal Year			Fiscal Year			Transition
								Period
		2013			2012			2011
		(52 weeks)			(52 weeks)			(52 weeks)
	Income tax provision (benefit)	$	6,683		$	(5,180	)	$	11,138
	Tax deficit on stock option exercises and restricted share vesting charged directly to common stock		254			576			639
		$	6,937		$	(4,604	)	$	11,777
Schedule of components of provision (benefit) for income taxes	'
	The provision (benefit) for income taxes consists of the following (in thousands):
		Fiscal Year			Fiscal Year			Fiscal Year
		2013			2012			2011
		(52 weeks)			(52 weeks)			(52 weeks)
	Currently payable:
	Federal	$	1,241		$	3,637		$	15,964
	Foreign		1,264			50			309
	State		254			1,015			3,604
			2,759			4,702			19,877
	Deferred:
	Federal		3,592			(8,163	)		(6,829	)
	Foreign		(238	)		21			(286	)
	State		570			(1,740	)		(1,624	)
		$	3,924		$	(9,882	)	$	(8,739	)
		$	6,683		$	(5,180	)	$	11,138
Schedule of reconciliation of tax rates with the federal statutory rate	'
		Fiscal Year			Fiscal Year			Fiscal Year
		2013			2012			2011
	Federal statutory rate		35	%		(35.0	)%		35	%
	State income taxes, net of federal income tax benefit		4.4			(1.3	)		7
	Goodwill impairment		—			20.6			—
	Foreign losses benefited		(2.8	)		(0.1	)		(3.0	)
	Losses not benefited		0.3			4.2			—
	Foreign rate differential		(0.4	)		2.1			0.9
	Foreign tax credit		(0.1	)		(0.5	)		(1.4	)
	Uncertain tax positions		(2.1	)		—			—
	Impact of NeuCo's tax provision charges		1.5			0.1			1.2
	Permanently disallowed expenses		1.6			1			1.5
	Other		(0.1	)		—			(1.5	)
			37.3	%		(8.9	)%		39.7	%
Schedule of components of deferred tax assets (liabilities)	'
	The components of CRA's deferred tax assets (liabilities) are as follows (in thousands):
		December 28,			December 29,
		2013			2012
	Deferred tax assets:
	Accrued compensation and related expense	$	21,064		$	16,743
	Tax basis in excess of financial basis of net accounts receivable		2,363			2,382
	Net operating loss carryforwards		5,421			6,682
	Tax basis in excess of financial basis of fixed assets		1,489			978
	Excess tax over book amortization		—			5,926
	Accrued expenses and other		902			2,565
	Total gross deferred tax assets		31,239			35,276
	Less: valuation allowance		(6,101	)		(7,287	)
	Total deferred tax assets net of valuation allowance		25,138			27,989
	Deferred tax liabilities:
	Tax basis in excess of financial basis of debentures		5,024			6,371
	Excess book over tax amortization		2,938			—
	Total deferred tax liabilities		7,962			6,371
	Net deferred tax assets	$	17,176		$	21,618
Schedule of aggregate changes in the balances of gross unrecognized tax benefits	'
	The aggregate changes in the balances of gross unrecognized tax benefits were as follows (in thousands):
		December 28,			December 29,
		2013			2012
	Balance at beginning of period	$	3,032		$	943
	Additions for tax positions taken during prior years		372			2,344
	Settlements with tax authorities		(3,032	)		(255	)
	Balance at end of the period	$	372		$	3,032

Restructuring_Charges_Tables

Restructuring Charges (Tables)	12 Months Ended
	Dec. 28, 2013
Restructuring Charges	'
Schedule of restructuring expenses and the reserve balance	'
	The restructuring expenses and reserve balance are as follows as of December 28, 2013 and December 29, 2012 (in thousands):
		Office			Employee			Total
		Vacancies			Workforce			Restructuring
					Reduction
	Balance at December 31, 2011	$	3,737		$	—		$	3,737
	Charges incurred during fiscal 2012		2,110			4,618			6,728
	Amounts paid, net of amounts received, during fiscal 2012		(3,514	)		(3,718	)		(7,232	)
	Non-cash adjustments and effect of foreign currency translation during fiscal 2012		(227	)		(27	)		(254	)
	Balance at December 29, 2012	$	2,106		$	873		$	2,979
	Charges incurred during fiscal 2013		—			—			—
	Amounts paid, net of amounts received, during fiscal 2013		(759	)		(729	)		(1,488	)
	Non-cash adjustments and effect of foreign currency translation during fiscal 2013		(177	)		(144	)		(321	)
	Balance at December 28, 2013	$	1,170		$	—		$	1,170

Quarterly_Financial_Data_Unaud1

Quarterly Financial Data (Unaudited) (Tables)	12 Months Ended
	Dec. 28, 2013
Quarterly Financial Data (Unaudited)	'
Schedule of quarterly financial data (unaudited)	'
		Quarter Ended
		March 30,		June 29,			September 28,			December 28,
		2013		2013			2013			2013
		(In thousands, except per share data)
	Revenues	$	63,130	$	65,203		$	74,427		$	75,672
	Gross profit		21,115		20,161			23,850			24,044
	Income from operations		3,774		3,170			6,114			5,459
	Income before provision for income taxes		3,377		3,368			5,952			5,221
	Net income		2,835		1,351			3,333			3,716
	Net (income) loss attributable to noncontrolling interest, net of tax		134		58			(63	)		6
	Net income attributable to CRA International, Inc.		2,969		1,409			3,270			3,722
	Basic net income per share	$	0.3	$	0.14		$	0.32		$	0.37
	Diluted net income per share	$	0.29	$	0.14		$	0.32		$	0.37
	Weighted average number of shares outstanding:
	Basic		9,994		10,100			10,093			10,071
	Diluted		10,084		10,188			10,192			10,148
		Quarter Ended
		March 31,		June 30,			September 29,			December 29,
		2012		2012			2012			2012
		(In thousands, except per share data)
	Revenues	$	69,132	$	67,813		$	65,912		$	67,533
	Gross profit		22,645		22,365			19,737			23,262
	Income (loss) from operations		3,306		2,808			1,035			(64,959	)
	Income (loss) before (provision) benefit for income taxes		3,253		2,695			1,016			(64,987	)
	Net income (loss)		436		773			(706	)		(53,346	)
	Net (income) loss attributable to noncontrolling interest, net of tax		83		(54	)		(38	)		(138	)
	Net income (loss) attributable to CRA International, Inc.		519		719			(744	)		(53,484	)
	Basic net income (loss) per share	$	0.05	$	0.07		$	(0.07	)	$	(5.33	)
	Diluted net income (loss) per share	$	0.05	$	0.07		$	(0.07	)	$	(5.33	)
	Weighted average number of shares outstanding:
	Basic		10,316		10,242			10,084			10,027
	Diluted		10,493		10,381			10,084			10,027

Summary_of_Significant_Account3

Summary of Significant Accounting Policies (Details) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Dec. 28, 2013	Sep. 28, 2013	Jun. 29, 2013	Mar. 30, 2013	Dec. 29, 2012	Sep. 29, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 28, 2013	Dec. 29, 2012	Dec. 31, 2011
									item	item	item
									segment
Description of Business	'	'	'	'	'	'	'	'	'	'	'
Number of broad areas of services	'	'	'	'	'	'	'	'	2	'	'
Number of business segments	'	'	'	'	'	'	'	'	1	'	'
Fiscal Year Change	'	'	'	'	'	'	'	'	'	'	'
Number of weeks periodically contained in a fiscal year	'	'	'	'	'	'	'	'	53	'	'
Number of weeks in a fiscal year	'	'	'	'	'	'	'	'	52	52	52
NeuCo Interest	'	'	'	'	'	'	'	'	'	'	'
Net revenue	$75,672	$74,427	$65,203	$63,130	$67,533	$65,912	$67,813	$69,132	$278,432	$270,390	$305,228
Net income (loss)	3,716	3,333	1,351	2,835	-53,346	-706	773	436	11,235	-52,843	16,945
Net income (loss) attributable to CRA International, Inc.	3,722	3,270	1,409	2,969	-53,484	-744	719	519	11,370	-52,990	16,851
NeuCo, Inc.	'	'	'	'	'	'	'	'	'	'	'
NeuCo Interest	'	'	'	'	'	'	'	'	'	'	'
Percentage of ownership interest held by the entity	'	'	'	'	'	'	'	'	55.89%	'	'
Net revenue	'	'	'	'	'	'	'	'	5,100	5,500	6,200
Net income (loss)	'	'	'	'	'	'	'	'	-300	300	200
Net income (loss) attributable to CRA International, Inc.	'	'	'	'	'	'	'	'	($200)	$200	$100

Summary_of_Significant_Account4

Summary of Significant Accounting Policies (Details 2) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 28, 2013	Dec. 29, 2012	Dec. 31, 2011
Revenue recognition	'	'	'
Reimbursable expenses	$37,320	$33,530	$39,722
Revenues | Fixed-price engagements	'	'	'
Revenue recognition	'	'	'
Percentage of consolidated revenues	13.00%	15.00%	22.00%
Minimum	'	'	'
Revenue recognition	'	'	'
Period in which engagements are generally completed	'3 months	'	'
Maximum	'	'	'
Revenue recognition	'	'	'
Period in which engagements are generally completed	'6 months	'	'

Summary_of_Significant_Account5

Summary of Significant Accounting Policies (Details 3) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 28, 2013	Dec. 29, 2012	Dec. 31, 2011
	segment
Goodwill	'	'	'
Number of reporting units	1	'	'
Goodwill impairment	$0	$71,394	$0
Minimum	'	'	'
Intangible assets	'	'	'
Remaining useful lives	'4 years	'	'
Maximum	'	'	'
Intangible assets	'	'	'
Remaining useful lives	'10 years	'	'

Summary_of_Significant_Account6

Summary of Significant Accounting Policies (Details 4)	12 Months Ended
	Dec. 28, 2013
Computer equipment	'
Property and equipment	'
Estimated useful lives	'3 years
Computer software | Minimum	'
Property and equipment	'
Estimated useful lives	'3 years
Computer software | Maximum	'
Property and equipment	'
Estimated useful lives	'10 years
Furniture and fixtures	'
Property and equipment	'
Estimated useful lives	'10 years

Summary_of_Significant_Account7

Summary of Significant Accounting Policies (Details 5) (USD $)	12 Months Ended
	Dec. 28, 2013	Dec. 29, 2012	Dec. 31, 2011
Roll forward of the accounts receivable allowance	'	'	'
Balance at beginning of period	$9,459,000	$6,548,000	'
Additions charged to revenues	5,644,000	6,808,000	'
Amounts written off	-7,891,000	-3,897,000	'
Balance at end of period	7,210,000	9,459,000	6,548,000
Foreign Currency Translation	'	'	'
Transaction gains and losses recorded in income (loss) before (provision) benefit for income taxes	-200,000	-200,000	-400,000
NeuCo, Inc.	'	'	'
Roll forward of the accounts receivable allowance	'	'	'
Change related to NeuCo	($2,000)	$0	'

Business_Acquisition_Details

Business Acquisition (Details)	Jan. 31, 2013
	item
Business Acquisition	'
Number of litigation consulting team members who joined the entity	40

Prepaid_Expenses_and_Other_Cur2

Prepaid Expenses and Other Current Assets, and Other Assets (Details) (USD $)	12 Months Ended		3 Months Ended
	Dec. 28, 2013	Dec. 29, 2012	Mar. 30, 2014
			Subsequent event
Prepaid expenses and other current assets	'	'	'
Term loans to employees and non-employee experts	$1,764,000	$8,614,000	'
Other	10,011,000	14,387,000	'
Total	11,775,000	23,001,000	'
Other assets	'	'	'
Forgivable loans to employees and non-employee experts	51,083,000	15,448,000	'
Other	3,538,000	6,223,000	'
Total	54,621,000	21,671,000	'
Prepaid expenses and other assets disclosures	'	'	'
Term of forgivable loans or advances to employees and non-employee experts, minimum	'3 years	'	'
Term of forgivable loans or advances to employees and non-employee experts, maximum	'8 years	'	'
Forgivable loans issuable to future employees for future service	5,000,000	'	'
Prepaid Expenses and Other Current Assets, and Other Assets	'	'	'
Forgivable loans issued to future employees for future service	$38,800,000	$20,700,000	$5,000,000

Goodwill_and_Intangible_Assets2

Goodwill and Intangible Assets (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 28, 2013	Dec. 29, 2012	Dec. 31, 2011
Changes in the carrying amount of goodwill	'	'	'
Balance at the beginning of the period, gross	$142,658	$141,153	'
Goodwill adjustments related to acquisitions	10,563	'	'
Goodwill adjustments related to sale of practice	'	-29	'
Goodwill adjustments related to NeuCo	-63	'	'
Effect of foreign currency translation	308	1,534	'
Balance at the end of the period, gross	153,466	142,658	141,153
Balance at the beginning of the period, Accumulated impairment losses	-71,893	-499	'
Goodwill impairment	0	-71,394	0
Balance at the end of the period, Accumulated impairment losses	-71,893	-71,893	-499
Balance at the beginning of the period, net	70,765	140,654	'
Balance at the end of the period, net	81,573	70,765	140,654
Intangible assets impairment losses	$0	$0	$0

Goodwill_and_Intangible_Assets3

Goodwill and Intangible Assets (Details 2) (USD $)	12 Months Ended
	Dec. 28, 2013	Dec. 29, 2012	Dec. 31, 2011
Acquired identifiable intangible assets	'	'	'
Acquired identifiable intangible assets, net of accumulated amortization	$4,537,000	$1,834,000	'
Accumulated amortization	8,392,000	7,122,000	'
Amortization of intangible assets	1,200,000	800,000	900,000
Amortization Expense	'	'	'
2014	1,111,000	'	'
2015	768,000	'	'
2016	579,000	'	'
2017	537,000	'	'
2018	512,000	'	'
Total	3,507,000	'	'
Non-competition agreements	'	'	'
Acquired identifiable intangible assets	'	'	'
Acquired identifiable intangible assets, net of accumulated amortization	598,000	1,047,000	'
Accumulated amortization	3,802,000	3,311,000	'
Customer relationships	'	'	'
Acquired identifiable intangible assets	'	'	'
Acquired identifiable intangible assets, net of accumulated amortization	3,909,000	691,000	'
Accumulated amortization	3,550,000	2,840,000	'
Other intangible assets	'	'	'
Acquired identifiable intangible assets	'	'	'
Acquired identifiable intangible assets, net of accumulated amortization	30,000	96,000	'
Accumulated amortization	$1,040,000	$971,000	'

Property_and_Equipment_Details

Property and Equipment (Details) (USD $)	12 Months Ended
	Dec. 28, 2013	Dec. 29, 2012	Dec. 31, 2011
Property and equipment	'	'	'
Property and equipment, gross	$54,210,000	$53,375,000	'
Accumulated depreciation and amortization	-38,555,000	-35,395,000	'
Property and equipment, net	15,655,000	17,980,000	'
Depreciation expense, including amounts recorded in costs of services	5,200,000	5,000,000	4,100,000
Computer, office equipment and software	'	'	'
Property and equipment	'	'	'
Property and equipment, gross	25,034,000	24,867,000	'
Leasehold improvements	'	'	'
Property and equipment	'	'	'
Property and equipment, gross	21,388,000	20,622,000	'
Furniture	'	'	'
Property and equipment	'	'	'
Property and equipment, gross	$7,788,000	$7,886,000	'

Accrued_Expenses_Details

Accrued Expenses (Details) (USD $)	12 Months Ended		3 Months Ended
	Dec. 28, 2013	Dec. 29, 2012	Mar. 30, 2014
			Subsequent event
Accrued Expenses	'	'	'
Compensation and related expenses	$51,960,000	$40,329,000	'
Income taxes payable	3,503,000	626,000	'
Other	10,194,000	4,350,000	'
Total	65,657,000	45,305,000	'
Accrued bonuses	40,000,000	28,000,000	'
Forgivable loans issuable to future employees for future service	5,000,000	'	'
Accrued Expenses	'	'	'
Forgivable loans issued to future employees for future service	$38,800,000	$20,700,000	$5,000,000

Credit_Agreement_Details

Credit Agreement (Details) (USD $)

12 Months Ended

0 Months Ended

12 Months Ended

3 Months Ended

Dec. 28, 2013

Dec. 29, 2012

Dec. 31, 2011

Apr. 24, 2013

Dec. 28, 2013

Dec. 28, 2013

Dec. 28, 2013

Dec. 28, 2013

Dec. 28, 2013

Dec. 28, 2013

Dec. 28, 2013

Dec. 28, 2013

Dec. 28, 2013

Jun. 29, 2013

Apr. 24, 2013

Revolving credit facility

Revolving credit facility

Revolving credit facility

Revolving credit facility

Revolving credit facility

Revolving credit facility

Revolving credit facility

Revolving credit facility

Revolving credit facility

Revolving credit facility

Multi currency portion

Letters of credit

Minimum

Maximum

Base rate

Base rate

Base rate

Eurocurrency rate

Eurocurrency rate

Eurocurrency rate

Minimum

Maximum

Minimum

Maximum

Senior Loan Agreement

'

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'

'

'

Revolving credit facility, maximum capacity

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$125,000,000

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'

'

'

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'

'

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'

$15,000,000

Borrowings under revolving line of credit

17,320,000

0

0

15,000,000

'

'

'

'

'

'

'

'

'

2,300,000

'

Amount outstanding under revolving line of credit

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'

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0

'

'

'

'

'

'

'

'

'

'

Amounts outstanding under letters of credit

400,000

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'

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400,000

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'

'

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'

'

Variable rate basis

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'base rate

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'eurocurrency rate

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'

'

Interest margin (as a percent)

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0.50%

1.50%

'

1.50%

2.50%

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'

Commitment fee payable on the unused portion of the credit facility (as a percent)

'

'

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0.25%

0.38%

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Percentage of stock of domestic subsidiaries pledged as collateral for borrowings

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100.00%

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Percentage of stock of foreign subsidiaries pledged as collateral for borrowings

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65.00%

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Value of stock in net assets pledged as collateral for borrowings

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$6,500,000

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Ratio of consolidated interest expense to consolidated EBITDA

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2.5

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Ratio of consolidated debt to consolidated EBITDA

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'

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3

'

'

'

'

'

'

'

'

'

'

Employee_Benefit_Plans_Details

Employee Benefit Plans (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 28, 2013	Dec. 29, 2012	Dec. 31, 2011
Employee Benefit Plans	'	'	'
Employer contributions under 401(k) plans	$1.70	$1.80	$2.70

Leases_Details

Leases (Details) (USD $)	12 Months Ended
	Dec. 28, 2013	Dec. 29, 2012	Dec. 31, 2011
Rental Commitments	'	'	'
2014	$13,912,000	'	'
2015	8,824,000	'	'
2016	4,038,000	'	'
2017	1,908,000	'	'
2018	850,000	'	'
Thereafter	17,000	'	'
Rental commitments, gross	29,549,000	'	'
Future minimum rentals under sublease arrangements	-2,918,000	'	'
Rental commitments	26,631,000	'	'
Additional disclosures	'	'	'
Rent expense	9,600,000	12,400,000	13,600,000
Restructuring charges	0	6,728,000	'
Standby letters of credit in support of the minimum future lease payments	400,000	'	'
Rent expense	'	'	'
Additional disclosures	'	'	'
Restructuring charges	$0	$900,000	$1,000,000

Net_Income_Loss_Per_Share_Deta

Net Income (Loss) Per Share (Details)	3 Months Ended								12 Months Ended
	Dec. 28, 2013	Sep. 28, 2013	Jun. 29, 2013	Mar. 30, 2013	Dec. 29, 2012	Sep. 29, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 28, 2013	Dec. 29, 2012	Dec. 31, 2011
Reconciliation of basic to diluted weighted average shares of common stock outstanding	'	'	'	'	'	'	'	'	'	'	'
Basic weighted average shares outstanding	10,071,000	10,093,000	10,100,000	9,994,000	10,027,000	10,084,000	10,242,000	10,316,000	10,084,000	10,167,000	10,555,000
Common stock equivalents:	'	'	'	'	'	'	'	'	'	'	'
Stock options and restricted stock (in shares)	'	'	'	'	'	'	'	'	89,000	0	184,000
Diluted weighted average shares outstanding	10,148,000	10,192,000	10,188,000	10,084,000	10,027,000	10,084,000	10,381,000	10,493,000	10,173,000	10,167,000	10,739,000
Calculation of common stock equivalents for purposes of computing diluted weighted average shares outstanding	'	'	'	'	'	'	'	'	'	'	'
Anti-dilutive securities excluded from EPS computation (in shares)	'	'	'	'	'	'	'	'	1,138,411	1,947,992	1,045,351
Additional anti-dilutive shares	'	'	'	'	'	'	'	'	'	140,000	'

Common_Stock_Details

Common Stock (Details) (USD $)	0 Months Ended				12 Months Ended
	Aug. 10, 2012	Feb. 22, 2012	Aug. 30, 2011	Jul. 06, 2010	Dec. 28, 2013	Dec. 29, 2012	Dec. 31, 2011
Share-Based Compensation	'	'	'	'	'	'	'
Share-based compensation expense	'	'	'	'	$2,900,000	$4,900,000	$5,700,000
Non-employee compensation expense	'	'	'	'	147,000	79,000	34,000
Employee tax withholdings paid on redemption of vested restricted shares	'	'	'	'	730,000	1,360,000	1,146,000
Common Stock Repurchases and Retirements	'	'	'	'	'	'	'
Share repurchase program, amount authorized to be repurchased	5,000,000	4,450,000	7,500,000	5,000,000	'	'	'
Number of shares repurchased and retired	'	'	'	'	118,968	466,109	398,372
Aggregate price of shares repurchased and retired	'	'	'	'	2,190,000	9,062,000	9,054,000
Amount available for future repurchases	'	'	'	'	1,400,000	'	'
Restricted shares	'	'	'	'	'	'	'
Share-Based Compensation	'	'	'	'	'	'	'
Vested (in shares)	'	'	'	'	134,384	216,528	164,086
Redemption of vested restricted shares in order to pay employee tax withholdings (in shares)	'	'	'	'	37,642	69,207	50,724
Employee tax withholdings paid on redemption of vested restricted shares	'	'	'	'	700,000	1,400,000	1,100,000
Employees and directors	'	'	'	'	'	'	'
Share-Based Compensation	'	'	'	'	'	'	'
Share-based compensation expense	'	'	'	'	$2,900,000	$4,900,000	$5,700,000

Common_Stock_Details_2

Common Stock (Details 2) (USD $)	0 Months Ended				12 Months Ended			0 Months Ended
	Aug. 10, 2012	Feb. 22, 2012	Aug. 30, 2011	Jul. 06, 2010	Dec. 28, 2013	Dec. 29, 2012	Dec. 31, 2011	Feb. 13, 2014
								Common Stock
								Subsequent event
								Maximum
Share repurchase program	'	'	'	'	'	'	'	'
Share repurchase program, amount authorized to be repurchased	$5,000,000	$4,450,000	$7,500,000	$5,000,000	'	'	'	$15,000,000
Options exercised (in shares)	'	'	'	'	'	'	'	'
Exercise of stock options (in shares)	'	'	'	'	13,389	47,185	47,009	'
Proceeds from exercise of options	'	'	'	'	200,000	600,000	600,000	'
Tax Deficit on Stock Option Exercises and Restricted Share Vesting	'	'	'	'	'	'	'	'
Tax deficits on stock options exercises and restricted share vestings	'	'	'	'	$254,000	$576,000	$639,000	'

ShareBased_Compensation_Detail

Share-Based Compensation (Details) (USD $)	12 Months Ended
	Dec. 28, 2013	Dec. 29, 2012	Dec. 31, 2011
Share-Based Compensation	'	'	'
Compensation expense	$2,900,000	$4,900,000	$5,700,000
Compensation expense, net of tax	1,900,000	3,000,000	3,500,000
Non-employee compensation expense, net of tax	$147,000	$79,000	$34,000
Weighted average fair market value (in dollars per share)	$7.77	'	'
Options granted (in shares)	262,463	0	'
Options	'	'	'
Share-Based Compensation	'	'	'
Weighted average fair market value (in dollars per share)	$7.77	'	$10.01
Options granted (in shares)	'	0	'
Weighted average assumptions	'	'	'
Risk-free interest rate (as a percent)	1.40%	'	1.00%
Expected volatility (as a percent)	47.00%	'	54.00%
Weighted average expected life	'5 years	'	'5 years
Expected dividends (as a percent)	0.00%	'	0.00%

ShareBased_Compensation_Detail1

Share-Based Compensation (Details 2)

12 Months Ended

12 Months Ended

26 Months Ended

44 Months Ended

96 Months Ended

12 Months Ended

Dec. 28, 2013

Dec. 29, 2012

Dec. 29, 2012

Dec. 28, 2013

Dec. 28, 2013

Dec. 28, 2013

Dec. 28, 2013

Dec. 28, 2013

Dec. 28, 2013

Dec. 28, 2013

Apr. 29, 2010

Mar. 12, 2008

Dec. 28, 2013

Dec. 28, 2013

Dec. 28, 2013

Dec. 28, 2013

Dec. 29, 2012

Options

2006 Incentive Plan

2006 Incentive Plan

2006 Incentive Plan

2006 Incentive Plan

2006 Incentive Plan

2006 Incentive Plan

2006 Incentive Plan

2006 Incentive Plan

2006 Incentive Plan

2006 Incentive Plan

2006 Incentive Plan

1998 Plan

1998 Plan

LTIP

On or after April 30, 2010

On or after March 12, 2008 and before April 30, 2010

Before March 12, 2008

Shares approved in 2008

Shares approved in 2010

Shares approved in 2012

Restricted shares or units

Restricted shares or units

Restricted shares or units

Options

Options

Options

Share-based compensation

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Fungibility ratio (as a percent)

'

'

'

'

183.00%

220.00%

180.00%

'

'

'

'

'

'

'

'

'

'

Actual Shares

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Restricted shares or units granted/reserved

'

'

'

'

'

'

'

'

'

'

352,932

471,827

1,196,776

'

'

'

'

Cancellation of restricted shares or units

'

'

'

'

'

'

'

'

'

'

91,964

91,277

302,374

'

'

'

'

Shares Using Fungibility Ratio

'

'

'

'

'

'

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'

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'

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'

'

'

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'

Maximum shares of common stock issuable

'

'

'

4,874,000

'

'

'

210,000

1,464,000

2,500,000

'

'

'

'

'

'

'

Shares initially reserved for issuance

'

'

'

500,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Restricted shares or units granted/reserved increase (decrease), available for grant

'

'

'

'

'

'

'

'

'

'

-776,450

-849,289

-2,190,100

'

'

'

'

Cancellation of restricted shares or units increase (decrease), available for grant

'

'

'

'

'

'

'

'

'

'

202,321

164,299

553,345

'

'

'

'

Options granted (in shares)

-262,463

0

0

'

'

'

'

'

'

'

'

'

'

-916,118

'

'

0

Options cancelled (in shares)

'

'

'

'

'

'

'

'

'

'

'

'

'

183,208

'

'

'

Options forfeited (in shares)

126,203

'

'

'

'

'

'

'

'

'

'

'

'

10,000

'

'

'

Shares available for grant

'

'

'

1,255,216

'

'

'

'

'

1,700,000

'

'

'

'

1,000,000

0

'

ShareBased_Compensation_Detail2

Share-Based Compensation (Details 3) (USD $)	12 Months Ended
	Dec. 28, 2013
Share-based compensation	'
Exercise price (in dollars per share)	$18.48
1998 Plan	'
Share-based compensation	'
Shares available for grant	1,000,000
1998 Plan | Options	'
Share-based compensation	'
Aggregate options granted (in shares)	3,839,216
Shares available for grant	0
1998 Plan | Options | Minimum	'
Share-based compensation	'
Termination period	'7 years
1998 Plan | Options | Maximum	'
Share-based compensation	'
Vesting period	'5 years
Termination period	'10 years
2004 Nonqualified Inducement Stock Option Plan | Options	'
Share-based compensation	'
Aggregate options granted (in shares)	359,420
Shares available for grant	0
2009 Nonqualified Inducement Stock Option Plan | Options	'
Share-based compensation	'
Aggregate options granted (in shares)	200,000
Vesting period	'4 years
Termination period	'7 years
Shares authorized	250,000
Shares available for grant	50,000
Exercise price (in dollars per share)	$50

ShareBased_Compensation_Detail3

Share-Based Compensation (Details 4) (USD $)	12 Months Ended
	Dec. 28, 2013	Dec. 29, 2012	Dec. 31, 2011
Options	'	'	'
Outstanding at the beginning of the period (in shares)	1,169,478	'	'
Granted (in shares)	262,463	0	'
Exercised (in shares)	-13,389	-47,185	-47,009
Forfeited (in shares)	-126,203	'	'
Outstanding at the end of the period (in shares)	1,292,349	1,169,478	'
Options exercisable at the end of the period (in shares)	890,671	'	'
Weighted Average Exercise Price	'	'	'
Outstanding at the beginning of the period (in dollars per share)	$32.33	'	'
Granted (in dollars per share)	$18.48	'	'
Exercised (in dollars per share)	$15.44	'	'
Forfeited (in dollars per share)	$24.84	'	'
Outstanding at the end of the period (in dollars per share)	$30.43	$32.33	'
Options exercisable at the end of the period (in dollars per share)	$35.28	'	'
Weighted Average Remaining Contractual Term	'	'	'
Outstanding at the end of the period	'3 years 4 months 17 days	'	'
Options exercisable at the end of the period	'2 years 1 month 24 days	'	'
Aggregate Intrinsic Value	'	'	'
Outstanding at the end of the period (in dollars)	$585,000	'	'
Options exercisable at the end of the period (in dollars)	0	'	'
Aggregate intrinsic value of stock options exercised	$100,000	$400,000	$600,000

ShareBased_Compensation_Detail4

Share-Based Compensation (Details 5) (USD $)	12 Months Ended
	Dec. 28, 2013
Options Outstanding	'
Number Outstanding (in shares)	1,292,349
Weighted-Average Remaining Contractual Life	'3 years 4 months 17 days
Weighted-Average Exercise Price (in dollars per share)	$30.43
Options Exercisable	'
Number Exercisable (in shares)	890,671
Weighted-Average Exercise Price (in dollars per share)	$35.28
Non-vested Options, Number of Shares	'
Balance at the beginning of the period (in shares)	301,576
Granted (in shares)	262,463
Vested (in shares)	-148,616
Forfeited (in shares)	-13,745
Balance at the end of the period (in shares)	401,678
Non-vested Options, Weighted-Average Fair Value	'
Balance at the beginning of the period (in dollars per share)	$8.89
Granted (in dollars per share)	$7.77
Vested (in dollars per share)	$8.82
Forfeited (in dollars per share)	$9.70
Balance at the end of the period (in dollars per share)	$8.16
$18.48	'
Options Outstanding	'
Number Outstanding (in shares)	262,463
Weighted-Average Remaining Contractual Life	'6 years 10 months 24 days
Weighted-Average Exercise Price (in dollars per share)	$18.48
Options Exercisable	'
Number Exercisable (in shares)	0
Weighted-Average Exercise Price (in dollars per share)	$0
$18.49 - 22.81	'
Share-based compensation	'
Exercise price, low end of range (in dollars per share)	$18.49
Exercise price, high end of range (in dollars per share)	$22.81
Options Outstanding	'
Number Outstanding (in shares)	350,385
Weighted-Average Remaining Contractual Life	'4 years 4 months 20 days
Weighted-Average Exercise Price (in dollars per share)	$21.67
Options Exercisable	'
Number Exercisable (in shares)	217,170
Weighted-Average Exercise Price (in dollars per share)	$21.62
$22.82 - 29.07	'
Share-based compensation	'
Exercise price, low end of range (in dollars per share)	$22.82
Exercise price, high end of range (in dollars per share)	$29.07
Options Outstanding	'
Number Outstanding (in shares)	116,062
Weighted-Average Remaining Contractual Life	'2 years 6 months 11 days
Weighted-Average Exercise Price (in dollars per share)	$25.05
Options Exercisable	'
Number Exercisable (in shares)	110,062
Weighted-Average Exercise Price (in dollars per share)	$25.05
$29.08 - 32.09	'
Share-based compensation	'
Exercise price, low end of range (in dollars per share)	$29.08
Exercise price, high end of range (in dollars per share)	$32.09
Options Outstanding	'
Number Outstanding (in shares)	53,502
Weighted-Average Remaining Contractual Life	'4 months 6 days
Weighted-Average Exercise Price (in dollars per share)	$32
Options Exercisable	'
Number Exercisable (in shares)	53,502
Weighted-Average Exercise Price (in dollars per share)	$32
$32.10 - 32.26	'
Share-based compensation	'
Exercise price, low end of range (in dollars per share)	$32.10
Exercise price, high end of range (in dollars per share)	$32.26
Options Outstanding	'
Number Outstanding (in shares)	148,623
Weighted-Average Remaining Contractual Life	'4 months 13 days
Weighted-Average Exercise Price (in dollars per share)	$32.26
Options Exercisable	'
Number Exercisable (in shares)	148,623
Weighted-Average Exercise Price (in dollars per share)	$32.26
$32.27 - 48.85	'
Share-based compensation	'
Exercise price, low end of range (in dollars per share)	$32.27
Exercise price, high end of range (in dollars per share)	$48.85
Options Outstanding	'
Number Outstanding (in shares)	70,250
Weighted-Average Remaining Contractual Life	'1 year 4 months 28 days
Weighted-Average Exercise Price (in dollars per share)	$39.65
Options Exercisable	'
Number Exercisable (in shares)	70,250
Weighted-Average Exercise Price (in dollars per share)	$39.65
$48.86 - 50.00	'
Share-based compensation	'
Exercise price, low end of range (in dollars per share)	$48.86
Exercise price, high end of range (in dollars per share)	$50
Options Outstanding	'
Number Outstanding (in shares)	150,000
Weighted-Average Remaining Contractual Life	'2 years 6 months 7 days
Weighted-Average Exercise Price (in dollars per share)	$50
Options Exercisable	'
Number Exercisable (in shares)	150,000
Weighted-Average Exercise Price (in dollars per share)	$50
$50.01 - 53.72	'
Share-based compensation	'
Exercise price, low end of range (in dollars per share)	$50.01
Exercise price, high end of range (in dollars per share)	$53.72
Options Outstanding	'
Number Outstanding (in shares)	141,064
Weighted-Average Remaining Contractual Life	'1 year 2 months 12 days
Weighted-Average Exercise Price (in dollars per share)	$50.87
Options Exercisable	'
Number Exercisable (in shares)	141,064
Weighted-Average Exercise Price (in dollars per share)	$50.87

ShareBased_Compensation_Detail5

Share-Based Compensation (Details 6) (USD $)	12 Months Ended
In Millions, except Share data, unless otherwise specified	Dec. 28, 2013	Dec. 29, 2012	Dec. 31, 2011
1998 Employee Stock Purchase Plan	'	'	'
Additional disclosures	'	'	'
Number of shares authorized	243,000	'	'
Purchase price as a percentage of fair market value	85.00%	'	'
Offering period	'1 year	'	'
Shares issued	0	0	0
Options	'	'	'
Additional disclosures	'	'	'
Fair value of options vested	1.3	1.5	1.1
Unrecognized compensation cost, net of expected forfeitures	3	'	'
Weighted-average period over which cost is expected to be recognized	'2 years 10 months 24 days	'	'
Additional disclosures	'	'	'
Vested shares outstanding that include the right of first refusal provision	175,277	'	'
Options exercisable that include the right of first refusal provision (in shares)	236,062	'	'
Restricted stock and stock units	'	'	'
Additional disclosures	'	'	'
Number of vesting installments	4	'	'
Unrecognized compensation cost, net of expected forfeitures	4.7	'	'
Weighted-average period over which cost is expected to be recognized	'2 years 9 months 18 days	'	'
Non-vested Restricted Stock and Stock Units, Number of Shares	'	'	'
Balance at the beginning of the period (in shares)	299,133	'	'
Granted (in shares)	155,403	'	'
Vested (in shares)	-134,384	-216,528	-164,086
Forfeited (in shares)	-11,114	'	'
Balance at the end of the period (in shares)	309,038	299,133	'
Non-vested Restricted Stock and Stock Units, Weighted-Average Fair Value	'	'	'
Balance at the beginning of the period (in dollars per share)	22.49	'	'
Granted (in dollars per share)	18.5	'	'
Vested (in dollars per share)	22.73	'	'
Forfeited (in dollars per share)	22.14	'	'
Balance at the end of the period (in dollars per share)	20.39	22.49	'
Additional disclosures	'	'	'
Number of shares issuable upon achievement of certain financial performance goals, specified period one	219,000	'	'

Business_Segment_and_Geographi2

Business Segment and Geographic Information (Details) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Dec. 28, 2013	Sep. 28, 2013	Jun. 29, 2013	Mar. 30, 2013	Dec. 29, 2012	Sep. 29, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 28, 2013	Dec. 29, 2012	Dec. 31, 2011
									segment
Business Segment and Geographic Information	'	'	'	'	'	'	'	'	'	'	'
Number of business segments	'	'	'	'	'	'	'	'	1	'	'
Business segment and geographic information	'	'	'	'	'	'	'	'	'	'	'
Revenue	$75,672	$74,427	$65,203	$63,130	$67,533	$65,912	$67,813	$69,132	$278,432	$270,390	$305,228
Long-lived assets (property and equipment, net)	15,655	'	'	'	17,980	'	'	'	15,655	17,980	'
United States	'	'	'	'	'	'	'	'	'	'	'
Business segment and geographic information	'	'	'	'	'	'	'	'	'	'	'
Revenue	'	'	'	'	'	'	'	'	216,815	207,779	224,661
Long-lived assets (property and equipment, net)	13,657	'	'	'	15,442	'	'	'	13,657	15,442	'
United Kingdom	'	'	'	'	'	'	'	'	'	'	'
Business segment and geographic information	'	'	'	'	'	'	'	'	'	'	'
Revenue	'	'	'	'	'	'	'	'	46,987	51,059	58,426
Long-lived assets (property and equipment, net)	1,911	'	'	'	2,452	'	'	'	1,911	2,452	'
Other	'	'	'	'	'	'	'	'	'	'	'
Business segment and geographic information	'	'	'	'	'	'	'	'	'	'	'
Revenue	'	'	'	'	'	'	'	'	14,630	11,552	22,141
Long-lived assets (property and equipment, net)	87	'	'	'	86	'	'	'	87	86	'
Total foreign	'	'	'	'	'	'	'	'	'	'	'
Business segment and geographic information	'	'	'	'	'	'	'	'	'	'	'
Revenue	'	'	'	'	'	'	'	'	61,617	62,611	80,567
Long-lived assets (property and equipment, net)	$1,998	'	'	'	$2,538	'	'	'	$1,998	$2,538	'

Income_Taxes_Details

Income Taxes (Details) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Dec. 28, 2013	Sep. 28, 2013	Jun. 29, 2013	Mar. 30, 2013	Dec. 29, 2012	Sep. 29, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 28, 2013	Dec. 29, 2012	Dec. 31, 2011
Income (loss) before (provision) benefit for income taxes:	'	'	'	'	'	'	'	'	'	'	'
U.S.	'	'	'	'	'	'	'	'	$13,659	($27,290)	$26,150
Foreign	'	'	'	'	'	'	'	'	4,259	-30,733	1,933
Income (loss) before (provision) benefit for income taxes	5,221	5,952	3,368	3,377	-64,987	1,016	2,695	3,253	17,918	-58,023	28,083
Components of income tax provision (benefit)	'	'	'	'	'	'	'	'	'	'	'
Income tax provision (benefit)	'	'	'	'	'	'	'	'	6,683	-5,180	11,138
Tax deficit on stock option exercises and restricted share vesting charged directly to common stock	'	'	'	'	'	'	'	'	254	576	639
Total	'	'	'	'	'	'	'	'	6,937	-4,604	11,777
Currently payable:	'	'	'	'	'	'	'	'	'	'	'
Federal	'	'	'	'	'	'	'	'	1,241	3,637	15,964
Foreign	'	'	'	'	'	'	'	'	1,264	50	309
State	'	'	'	'	'	'	'	'	254	1,015	3,604
Currently payable	'	'	'	'	'	'	'	'	2,759	4,702	19,877
Deferred:	'	'	'	'	'	'	'	'	'	'	'
Federal	'	'	'	'	'	'	'	'	3,592	-8,163	-6,829
Foreign	'	'	'	'	'	'	'	'	-238	21	-286
State	'	'	'	'	'	'	'	'	570	-1,740	-1,624
Deferred	'	'	'	'	'	'	'	'	3,924	-9,882	-8,739
Provision (benefit) for income taxes	'	'	'	'	'	'	'	'	$6,683	($5,180)	$11,138
Reconciliation of tax rates with federal statutory rate	'	'	'	'	'	'	'	'	'	'	'
Federal statutory rate (as a percent)	'	'	'	'	'	'	'	'	35.00%	-35.00%	35.00%
State income taxes, net of federal income tax benefit (as a percent)	'	'	'	'	'	'	'	'	4.40%	-1.30%	7.00%
Goodwill impairment (as a percent)	'	'	'	'	'	'	'	'	0.00%	20.60%	0.00%
Foreign losses benefited (as a percent)	'	'	'	'	'	'	'	'	-2.80%	-0.10%	-3.00%
Losses not benefited (as a percent)	'	'	'	'	'	'	'	'	0.30%	4.20%	0.00%
Foreign rate differential (as a percent)	'	'	'	'	'	'	'	'	-0.40%	2.10%	0.90%
Foreign tax credit (as a percent)	'	'	'	'	'	'	'	'	-0.10%	-0.50%	-1.40%
Uncertain tax positions (as a percent)	'	'	'	'	'	'	'	'	-2.10%	0.00%	0.00%
Impact of NeuCo's tax provision charges (as a percent)	'	'	'	'	'	'	'	'	1.50%	0.10%	1.20%
Permanently disallowed expenses (as a percent)	'	'	'	'	'	'	'	'	1.60%	1.00%	1.50%
Other (as a percent)	'	'	'	'	'	'	'	'	-0.10%	0.00%	-1.50%
Effective tax rate (as a percent)	'	'	'	'	'	'	'	'	37.30%	-8.90%	39.70%

Income_Taxes_Details_2

Income Taxes (Details 2) (USD $)	12 Months Ended
	Dec. 28, 2013	Dec. 29, 2012
Deferred tax assets:	'	'
Accrued compensation and related expense	$21,064,000	$16,743,000
Tax basis in excess of financial basis of net accounts receivable	2,363,000	2,382,000
Net operating loss carryforwards	5,421,000	6,682,000
Tax basis in excess of financial basis of fixed assets	1,489,000	978,000
Excess tax over book amortization	'	5,926,000
Accrued expenses and other	902,000	2,565,000
Total gross deferred tax assets	31,239,000	35,276,000
Less: valuation allowance	-6,101,000	-7,287,000
Total deferred tax assets net of valuation allowance	25,138,000	27,989,000
Deferred tax liabilities:	'	'
Tax basis in excess of financial basis of debentures	5,024,000	6,371,000
Excess book over tax amortization	2,938,000	'
Total deferred tax liabilities	7,962,000	6,371,000
Net deferred tax assets	17,176,000	21,618,000
Valuation allowance	'	'
Net change in valuation allowance	-1,200,000	2,300,000
Increase in deferred tax liability associated with goodwill and a corresponding decrease to valuation allowance	1,400,000	'
Net operating losses	'	'
Valuation allowance	'	'
Net change in valuation allowance	-600,000	-200,000
Net operating losses | NeuCo, Inc.	'	'
Valuation allowance	'	'
Net change in valuation allowance	-400,000	'
Net operating losses | Foreign	'	'
Valuation allowance	'	'
Net change in valuation allowance	($400,000)	$2,500,000

Income_Taxes_Details_3

Income Taxes (Details 3) (USD $)	Dec. 28, 2013
Foreign	'
Operating loss carryforwards	'
Net operating loss carryforwards	$11,800,000
Operating losses subject to expiration	200,000
U.S. state	'
Operating loss carryforwards	'
Net operating loss carryforwards	400,000
U.S. federal and U.S. state | NeuCo, Inc.	'
Operating loss carryforwards	'
Net operating loss carryforwards	6,100,000
Federal | NeuCo, Inc.	'
Operating loss carryforwards	'
Operating losses available to offset the entity's consolidated taxable income	$0

Income_Taxes_Details_4

Income Taxes (Details 4) (USD $)	12 Months Ended
	Dec. 28, 2013	Dec. 29, 2012
Changes in the balances of gross unrecognized tax benefits	'	'
Balance at beginning of period	$3,032,000	$943,000
Additions for tax positions taken during prior years	372,000	2,344,000
Settlements with tax authorities	-3,032,000	-255,000
Balance at end of the period	372,000	3,032,000
Interest on unrecognized tax benefits	67,000	'
Unrecognized tax benefits being recognized as a reduction to the effective income tax rate	47,000	'
Unrecognized tax benefits	'	'
Amount of unrecognized tax benefits that is reasonably possible to be reversed within the next twelve months	47,000	'
Additional disclosures	'	'
Undistributed earnings from foreign subsidiaries	$3,200,000	'

RelatedParty_Transactions_Deta

Related-Party Transactions (Details) (Shareholders, USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 28, 2013	Dec. 29, 2012	Dec. 31, 2011
Shareholders	'	'	'
Related-Party Transactions	'	'	'
Payments for consulting services	$6.10	$5.40	$7.30

Restructuring_Charges_Details

Restructuring Charges (Details) (USD $)

12 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

Dec. 28, 2013

Dec. 29, 2012

Dec. 28, 2013

Dec. 28, 2013

Dec. 28, 2013

Dec. 29, 2012

Dec. 28, 2013

Dec. 29, 2012

Jun. 30, 2012

Dec. 29, 2012

Jun. 30, 2012

Jun. 30, 2012

Dec. 29, 2012

Dec. 29, 2012

Dec. 29, 2012

Dec. 29, 2012

Dec. 28, 2013

Deferred rent and other non-current liabilities

Current portion of deferred rent

Office Vacancies

Office Vacancies

Employee Workforce Reduction

Employee Workforce Reduction

London office surrender

London office surrender

London office surrender

London office surrender

Houston office space adjustments

Houston office space adjustments

Houston office space adjustments

Houston office space adjustments

Restructuring Plan, July 2012

item

Lease surrender

Other restructuring

Cost of sales

Selling, general and administrative expenses

Depreciation and amortization expense

Minimum

service

Restructuring charges disclosures

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Restructuring charges related to termination benefits, facility related charges, asset write downs and other charges

'

$5,400,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Number of consulting positions reduced under the plan

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

60

Number of floors under lease surrendered

'

'

'

'

'

'

'

'

'

1

'

'

'

'

'

'

'

Number of floors under lease

'

'

'

'

'

'

'

'

'

3

'

'

'

'

'

'

'

Amount paid for lease surrender

1,488,000

7,232,000

'

'

759,000

3,514,000

729,000

3,718,000

'

'

1,200,000

'

'

'

'

'

'

Pre-tax restructuring credit related to adjustments of leased office space in Houston, TX

'

'

'

'

'

'

'

'

'

'

'

'

400,000

'

'

'

'

Restructuring expenses and reserve balance

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Balance at the beginning of the period

2,979,000

3,737,000

400,000

800,000

2,106,000

3,737,000

873,000

0

'

'

'

'

'

'

'

'

'

Charges incurred

0

6,728,000

'

'

0

2,110,000

0

4,618,000

1,700,000

'

'

500,000

6,700,000

3,800,000

1,500,000

1,400,000

'

Amounts paid, net of amounts received, during fiscal 2013

-1,488,000

-7,232,000

'

'

-759,000

-3,514,000

-729,000

-3,718,000

'

'

-1,200,000

'

'

'

'

'

'

Non-cash adjustments and effect of foreign currency translation

-321,000

-254,000

'

'

-177,000

-227,000

-144,000

-27,000

'

'

'

'

'

'

'

'

'

Balance at the end of the period

$1,170,000

$2,979,000

$400,000

$800,000

$1,170,000

$2,106,000

$0

$873,000

'

'

'

'

'

'

'

'

'

Quarterly_Financial_Data_Unaud2

Quarterly Financial Data (Unaudited) (Details) (USD $)	3 Months Ended								12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 28, 2013	Sep. 28, 2013	Jun. 29, 2013	Mar. 30, 2013	Dec. 29, 2012	Sep. 29, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 28, 2013	Dec. 29, 2012	Dec. 31, 2011
									item
Quarterly Financial Data (Unaudited)	'	'	'	'	'	'	'	'	'	'	'
Revenues	$75,672	$74,427	$65,203	$63,130	$67,533	$65,912	$67,813	$69,132	$278,432	$270,390	$305,228
Gross profit	24,044	23,850	20,161	21,115	23,262	19,737	22,365	22,645	89,170	88,009	105,845
Income (loss) from operations	5,459	6,114	3,170	3,774	-64,959	1,035	2,808	3,306	18,517	-57,810	29,064
Income (loss) before (provision) benefit for income taxes	5,221	5,952	3,368	3,377	-64,987	1,016	2,695	3,253	17,918	-58,023	28,083
Net income (loss)	3,716	3,333	1,351	2,835	-53,346	-706	773	436	11,235	-52,843	16,945
Net (income) loss attributable to noncontrolling interest, net of tax	6	-63	58	134	-138	-38	-54	83	135	-147	-94
Net income (loss) attributable to CRA International, Inc.	$3,722	$3,270	$1,409	$2,969	($53,484)	($744)	$719	$519	$11,370	($52,990)	$16,851
Basic net income (loss) per share (in dollars per share)	$0.37	$0.32	$0.14	$0.30	($5.33)	($0.07)	$0.07	$0.05	$1.13	($5.21)	$1.60
Diluted net income (loss) per share (in dollars per share)	$0.37	$0.32	$0.14	$0.29	($5.33)	($0.07)	$0.07	$0.05	$1.12	($5.21)	$1.57
Weighted average number of shares outstanding:	'	'	'	'	'	'	'	'	'	'	'
Basic (in shares)	10,071	10,093	10,100	9,994	10,027	10,084	10,242	10,316	10,084	10,167	10,555
Diluted (in shares)	10,148	10,192	10,188	10,084	10,027	10,084	10,381	10,493	10,173	10,167	10,739
Number of quarters the sum of which may not equal the full year amount	'	'	'	'	'	'	'	'	4	'	'

Subsequent_Event_Details

Subsequent Event (Details) (Subsequent event, USD $)	0 Months Ended
In Millions, unless otherwise specified	Feb. 24, 2014
	item
	sqft
Subsequent event	'
Subsequent Events	'
Area of office building taken on lease	57,602
Initial term of the lease	'10 years
Number of options available for lease extensions	2
Period for which lease tem can be extended	'5 years
Annual fixed rent per square foot for the first year of the lease's base term	42
Threshold amount of annual fixed rent for the first year of the lease's base term	$2.40
Incremental annual fixed rent per square foot for remainder of the lease's base term	1
Amount of letters of credit issued as security	1
Area of office space not included in amendment	25,099
Amount of base rent payable extension period, if term of the existing lease is extended	$2.40