Exponent (EXPO) 10-Q 3 Aug 18 2018 Q2 Quarterly report Financial data

Document And Entity Information

Document And Entity Information - shares	6 Months Ended
	Jun. 29, 2018	Jul. 27, 2018
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 29, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q2
Entity Registrant Name	EXPONENT INC
Entity Central Index Key	851,520
Current Fiscal Year End Date	--12-28
Entity Filer Category	Large Accelerated Filer
Trading Symbol	EXPO
Entity Common Stock, Shares Outstanding		52,037,529

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 29, 2018	Dec. 29, 2017
Current assets:
Cash and cash equivalents	$ 117,773	$ 124,794
Short-term investments	75,534	71,604
Accounts receivable, net of allowance for contract losses and doubtful accounts of $3,644 and $3,526 at June 29, 2018 and December 29, 2017, respectively	116,532	110,100
Prepaid expenses and other assets	9,184	9,011
Total current assets	319,023	315,509
Property, equipment and leasehold improvements, net	41,357	35,014
Goodwill	8,607	8,607
Deferred income taxes	31,824	30,437
Deferred compensation plan assets	53,801	48,676
Other assets	1,081	1,346
Total assets	455,693	439,589
Current liabilities:
Accounts payable and accrued liabilities	12,403	14,741
Accrued payroll and employee benefits	56,843	70,064
Deferred revenues	8,007	8,302
Total current liabilities	77,253	93,107
Other liabilities	3,225	3,326
Deferred compensation	55,310	52,776
Deferred rent	1,139	1,292
Total liabilities	136,927	150,501
Stockholders’ equity:
Common stock, $0.001 par value; 120,000 shares authorized; 65,707 shares issued at June 29, 2018 and December 29, 2017	66	66
Additional paid-in capital	223,696	210,230
Accumulated other comprehensive income (loss)
Investment securities, available-for-sale	(257)	(236)
Foreign currency translation adjustments	(2,422)	(1,793)
Accumulated other comprehensive income (loss)	(2,679)	(2,029)
Retained earnings	322,437	303,990
Treasury stock, at cost; 13,669 and 14,169 shares held at June 29, 2018 and December 29, 2017, respectively	(224,754)	(223,169)
Total stockholders’ equity	318,766	289,088
Total liabilities and stockholders’ equity	$ 455,693	$ 439,589

Condensed Consolidated Balance3

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) shares in Thousands, $ in Thousands	Jun. 29, 2018	Dec. 29, 2017
Accounts receivable, net of allowance for contract losses and doubtful accounts	$ 3,644	$ 3,526
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	120,000	120,000
Common stock, shares issued	65,707	65,707
Treasury stock, shares	13,669	14,169

Condensed Consolidated Statemen

Condensed Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 29, 2018	Jun. 30, 2017	Jun. 29, 2018	Jun. 30, 2017
Revenues:
Revenues before reimbursements	$ 89,972	$ 84,120	$ 180,656	$ 164,587
Reimbursements	5,649	3,720	11,422	7,375
Revenues	95,621	87,840	192,078	171,962
Operating expenses:
Compensation and related expenses	55,458	51,536	113,037	105,954
Other operating expenses	7,566	7,275	15,031	14,466
Reimbursable expenses	5,649	3,720	11,422	7,375
General and administrative expenses	4,470	4,992	8,512	9,216
Total operating expenses	73,143	67,523	148,002	137,011
Operating income	22,478	20,317	44,076	34,951
Other income, net:
Interest income, net	543	266	1,073	500
Miscellaneous income, net	1,898	1,765	2,220	4,307
Total other income, net	2,441	2,031	3,293	4,807
Income before income taxes	24,919	22,348	47,369	39,758
Income taxes	6,494	8,557	8,604	9,391
Net income	$ 18,425	$ 13,791	$ 38,765	$ 30,367
Net income per share:
Basic	$ 0.35	$ 0.26	$ 0.73	$ 0.58
Diluted	$ 0.34	$ 0.26	$ 0.72	$ 0.56
Shares used in per share computations:
Basic	53,008	52,830	52,876	52,716
Diluted	54,195	53,936	54,111	53,960
Cash dividends declared per common share	$ 0.13	$ 0.105	$ 0.26	$ 0.21

Condensed Consolidated Stateme5

Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 29, 2018	Jun. 30, 2017	Jun. 29, 2018	Jun. 30, 2017
Net income	$ 18,425	$ 13,791	$ 38,765	$ 30,367
Other comprehensive income (loss):
Foreign currency translation adjustments, net of tax	(1,368)	454	(629)	590
Unrealized gains (losses) on available-for- sale investment securities arising during the period, net of tax	19	(32)	(21)	4
Comprehensive income	$ 17,076	$ 14,213	$ 38,115	$ 30,961

Condensed Consolidated Stateme6

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 29, 2018	Jun. 30, 2017
Cash flows from operating activities:
Net income	$ 38,765	$ 30,367
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization of property, equipment and leasehold improvements	3,149	3,195
Amortization of premiums and accretion of discounts on short-term investments	(19)	0
Deferred rent	(153)	(205)
Provision for contract losses and doubtful accounts	782	805
Stock-based compensation	10,033	9,187
Deferred income tax provision	(1,379)	1,217
Changes in operating assets and liabilities:
Accounts receivable	(7,214)	(20,840)
Prepaid expenses and other assets	(4,553)	3,365
Accounts payable and accrued liabilities	(3,018)	928
Accrued payroll and employee benefits	(8,182)	(9,806)
Deferred revenues	(295)	(1,022)
Net cash provided by operating activities	27,916	17,191
Cash flows from investing activities:
Capital expenditures	(8,949)	(2,526)
Purchase of short-term investments	(19,939)	(13,000)
Maturity of short-term investments	16,000	0
Net cash used in investing activities	(12,888)	(15,526)
Cash flows from financing activities:
Payroll taxes for restricted stock units	(8,637)	(9,520)
Repurchase of common stock	0	(7,004)
Exercise of share-based payment awards	692	638
Dividends and dividend equivalents rights	(13,732)	(10,995)
Net cash used in financing activities	(21,677)	(26,881)
Effect of foreign currency exchange rates on cash and cash equivalents	(372)	482
Net decrease in cash and cash equivalents	(7,021)	(24,734)
Cash and cash equivalents at beginning of period	124,794	114,967
Cash and cash equivalents at end of period	$ 117,773	$ 90,233

Basis of Presentation

Basis of Presentation	6 Months Ended
	Jun. 29, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Note 1: Basis of Presentation Exponent, Inc. (referred to as the “Company” or “Exponent”) is an engineering and scientific consulting firm that provides solutions to complex problems. The Company operates on a 52-53 week fiscal year ending on the Friday closest to the last day of December. The accompanying unaudited condensed consolidated financial statements are prepared in accordance with accounting principles generally accepted in the United States of America for interim financial information, the instructions to Form 10-Q and Article 10 of Regulation S-X promulgated by the Securities and Exchange Commission. Accordingly, they do not contain all the information and notes required by accounting principles generally accepted in the United States of America for complete financial statements. In the opinion of management, all adjustments which are necessary for the fair presentation of the condensed consolidated financial statements have been included and all such adjustments are of a normal and recurring nature. The operating results for the three and six months ended June 29, 2018 are not necessarily representative of the results of future quarterly or annual periods. The following information should be read in conjunction with the audited consolidated financial statements and accompanying notes thereto included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 29, 2017, which was filed with the U.S. Securities and Exchange Commission on February 23, 2018. The unaudited condensed consolidated financial statements include the accounts of Exponent, Inc. and its subsidiaries, which are all wholly owned. All intercompany accounts and transactions have been eliminated in consolidation. Stock Split. Dividend. Fiscal Year 2018 Dividends Amount Per Share (in thousands) First Quarter $ 0.13 $ 6,700 Second Quarter 0.13 6,764 Total $ 0.26 $ 13,464 Fiscal Year 2017 Dividends Amount Per Share (in thousands) First Quarter $ 0.105 $ 5,374 Second Quarter 0.105 5,424 Third Quarter 0.105 5,424 Fourth Quarter 0.105 5,416 Total $ 0.420 $ 21,638 On July 19, 2018, the Company’s Board of Directors announced a cash dividend of $0.13 per share of the Company’s common stock, payable September 21, 2018 to stockholders of record as of September 7, 2018. The Company expects to continue paying quarterly dividends in the future, subject to declaration by the Company’s Board of Directors. Use of Estimates. The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions 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 revenues and expenses during the period. Items subject to such estimates and assumptions include accounting for revenue recognition and estimating the allowance for contract losses and doubtful accounts. Actual results could differ from those estimates. Recently Adopted Accounting Pronouncements Revenue from Contracts with Customers Recent Accounting Pronouncements Not Yet Effective Leases

Revenue Recognition

Revenue Recognition	6 Months Ended
	Jun. 29, 2018
Revenue Recognition [Abstract]
Revenue Recognition	Note 2: Revenue Recognition Substantially all of the Company’s engagements are performed under time and material or fixed-price arrangements. For time and materials contracts, the Company utilizes the practical expedient under the ASU which states, if an entity has a right to consideration from a customer in an amount that corresponds directly with the value of the entity’s performance completed to date (for example, a service contract in which an entity bills a fixed amount for each hour of service provided), the entity may recognize revenue in the amount to which the entity has a right to invoice. During the second quarter of fiscal 2018, the Company recognized revenue of $ 79,965,000 84 62,347,000 17,618,000 163,136,000 85 126,948,000 36,188,000 For fixed price contracts, the Company recognizes revenue over time under the ASU because of the continuous transfer of control to the customer. The customer typically controls the work in process as evidenced either by contractual termination clauses or by the Company’s rights to payment for work performed to date to deliver services that do not have an alternative use to the Company. Revenue for fixed price contracts is recognized based on the relationship of incurred labor hours at standard rates to the Company’s estimate of the total labor hours at standard rates it expects to incur over the term of the contract. The Company believes this methodology achieves a reliable measure of the revenue from the consulting services it provides to its customers under fixed-price contracts given the nature of the consulting services the Company provides and the following additional considerations: ⋅ the Company considers labor hours at standard rates and expenses to be incurred when pricing its contracts; ⋅ the Company generally does not incur set up costs on its contracts; ⋅ the Company does not believe that there are reliable milestones to measure progress towards completion; ⋅ if the contract is terminated early, the customer is required to pay the Company for time at standard rates plus materials incurred to date; ⋅ the Company’s contracts do not include award fees or bonuses; ⋅ the Company does not include revenue for unpriced change orders until the customer agrees with the changes; ⋅ historically the Company has not had significant accounts receivable write-offs or cost overruns; and ⋅ its contracts are typically progress billed on a monthly basis. During the second quarter of fiscal 2018, the Company recognized revenue of $ 15,656,000 16 14,733,000 923,000 28,942,000 15 27,179,000 1,763,000 Deferred revenues represent amounts billed to clients in advance of services provided. During the second quarter of fiscal 2018, $ 2,671,000 4,604,000 Reimbursements, including those related to travel and other out-of-pocket expenses, and other similar third party costs such as the cost of materials and certain subcontracts, are included in revenues, and an equivalent amount of reimbursable expenses are included in operating expenses. Any mark-up on reimbursable expenses is included in revenues. The Company reports revenues net of subcontractor fees for certain subcontracts where the Company has determined that it is acting as an agent because its performance obligation is to arrange for the provision of goods or services by another party. The total amount of subcontractor fees not included in revenues because the Company was acting as an agent were $ 5.8 11.4

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 29, 2018
Fair Value Disclosures [Abstract]
Fair Value Measurements	Note 3: Fair Value Measurements The Company measures certain financial assets and liabilities at fair value on a recurring basis, including available-for-sale fixed income securities, trading fixed income and equity securities held in its deferred compensation plan and the liability associated with its deferred compensation plan. There were no transfers between fair value measurement levels during the three and six months ended June 29, 2018 and June 30, 2017. Any transfers between fair value measurement levels would be recorded on the actual date of the event or change in circumstances that caused the transfer. The fair value of these certain financial assets and liabilities was determined using the following inputs at June 29, 2018: Fair Value Measurements at Reporting Date Using (In thousands) Total Quoted Prices in Significant Other Significant Assets Money market securities (1) $ 6,267 $ 6,267 $ - $ - Fixed income available-for-sale securities (2) 75,534 - 75,534 - Fixed income trading securities held in deferred compensation plan (3) 16,419 16,419 - - Equity trading securities held in deferred compensation plan (3) 42,068 42,068 - - Total $ 140,288 $ 64,754 $ 75,534 $ - Liabilities Deferred compensation plan (4) 62,196 62,196 - - Total $ 62,196 $ 62,196 $ - $ - (1) Included in cash and cash equivalents on the Company’s unaudited condensed consolidated balance sheet. (2) Included in short-term investments on the Company’s unaudited condensed consolidated balance sheet. (3) Included in prepaid expenses and other assets and deferred compensation plan assets on the Company’s unaudited condensed consolidated balance sheet. (4) Included in accrued payroll and employee benefits and deferred compensation on the Company’s unaudited condensed consolidated balance sheet. The fair value of these certain financial assets and liabilities was determined using the following inputs at December 29, 2017: Fair Value Measurements at Reporting Date Using (In thousands) Total Quoted Prices in Significant Other Significant Assets Money market securities (1) $ 9,742 $ 9,742 $ - $ - Fixed income available- for-sale securities (2) 71,604 - 71,604 - Fixed income trading securities held in deferred compensation plan (3) 13,686 13,686 - - Equity trading securities held in deferred compensation plan (3) 39,664 39,664 - - Total $ 134,696 $ 63,092 $ 71,604 $ - Liabilities Deferred compensation plan (4) 59,050 59,050 - - Total $ 59,050 $ 59,050 $ - $ - (1) Included in cash and cash equivalents on the Company’s unaudited condensed consolidated balance sheet. (2) Included in short-term investments on the Company’s unaudited condensed consolidated balance sheet. (3) Included in prepaid expenses and other assets and deferred compensation plan assets on the Company’s unaudited condensed consolidated balance sheet. (4) Included in accrued payroll and employee benefits and deferred compensation on the Company’s unaudited condensed consolidated balance sheet. Fixed income available-for-sale securities as of June 29, 2018 and December 29, 2017 represent obligations of the United States Treasury and United States agencies. Fixed income and equity trading securities represent mutual funds held in the Company’s deferred compensation plan. See Note 7 for additional information about the Company’s deferred compensation plan. Amortized Unrealized Unrealized Estimated (In thousands) Cost Gains Losses Fair Value Classified as current assets: Cash $ 111,506 $ - $ - $ 111,506 Cash equivalents: Money market securities 6,267 - - 6,267 Total cash equivalents 6,267 - - 6,267 Total cash and cash equivalents 117,773 - - 117,773 Short-term investments: U.S. Treasury and agency securities 75,955 - (421) 75,534 Total short-term investments 75,955 - (421) 75,534 Total cash, cash equivalents and short-term investments $ 193,728 $ - $ (421) $ 193,307 Cash, cash equivalents and short-term investments consisted of the following as of December 29, 2017: Amortized Unrealized Unrealized Estimated (In thousands) Cost Gains Losses Fair Value Classified as current assets: Cash $ 115,052 $ - $ - $ 115,052 Cash equivalents: Money market securities 9,742 - - 9,742 Total cash equivalents 9,742 - - 9,742 Total cash and cash equivalents 124,794 - - 124,794 Short-term investments: U.S. Treasury and agency securities 71,997 - (393) 71,604 Total short-term investments 71,997 - (393) 71,604 Total cash, cash equivalents and short-term investments $ 196,791 $ - $ (393) $ 196,398 Amortized Estimated (In thousands) Cost Fair Value Due within one year $ 43,947 $ 43,784 Due between one and two years 32,008 31,750 Total $ 75,955 $ 75,534 At June 29, 2018 and December 29, 2017, the Company did not have any assets or liabilities valued using significant unobservable inputs. The following financial instruments are not measured at fair value on the Company's condensed consolidated balance sheet at June 29, 2018 and December 29, 2017, but require disclosure of their fair values: accounts receivable, other assets and accounts payable. The estimated fair value of such instruments at June 29, 2018 and December 29, 2017 approximates their carrying value as reported on the condensed consolidated balance sheet. There were no other-than-temporary impairments or credit losses related to available-for-sale securities during the three and six months ended June 29, 2018 and June 30, 2017.

Net Income Per Share

Net Income Per Share	6 Months Ended
	Jun. 29, 2018
Earnings Per Share [Abstract]
Net Income Per Share	Note 4: Net Income Per Share Basic per share amounts are computed using the weighted-average number of common shares outstanding during the period. Diluted per share amounts are calculated using the weighted-average number of common shares outstanding during the period and, when dilutive, the weighted-average number of potential common shares from the issuance of common stock to satisfy outstanding restricted stock units and the exercise of outstanding options to purchase common stock using the treasury stock method. Three Months Ended Six Months Ended (In thousands) June 29, June 30, June 29, June 30, Shares used in basic per share computation 53,008 52,830 52,876 52,716 Effect of dilutive common stock options outstanding 398 270 362 266 Effect of dilutive restricted stock units outstanding 789 836 873 978 Shares used in diluted per share computation 54,195 53,936 54,111 53,960 There were no options excluded from the diluted per share calculations for the three and six months ended June 29, 2018 and June 30, 2017.

Stock-Based Compensation

Stock-Based Compensation	6 Months Ended
	Jun. 29, 2018
Share-based Compensation [Abstract]
Stock-Based Compensation	Note 5: Stock-Based Compensation Restricted Stock Units Restricted stock unit grants are designed to attract and retain employees, and to better align employee interests with those of the Company’s stockholders. For a select group of employees, up to 40 The value of these restricted stock unit awards is determined based on the market price of the Company’s common stock on the date of grant. The value of fully vested restricted stock unit awards issued is recorded as a reduction to accrued bonuses. The portion of bonus expense that the Company expects to settle with fully vested restricted stock unit awards is recorded as stock-based compensation during the period the bonus is earned. The Company recorded stock-based compensation expense associated with accrued bonus awards of $ 2,168,000 2,201,000 4,400,000 4,129,000 59 1,460,000 1,238,000 4,968,000 4,494,000 Stock Options Stock options are granted for terms of ten years and generally vest 25% per year over a four-year period from the grant date. Unvested stock option awards will continue to vest in the case of retirement at 59½ years or older, provided that the holder of each award does all consulting work through the Company and does not become an employee for a past or present client, beneficial party or competitor of the Company. The value of the unvested stock option awards granted is recognized on a straight-line basis over the shorter of the four-year vesting period or the period between the grant date and the date the award recipient turns 59½. If the award recipient is 59½ years or older on the date of grant, the value of the entire award is expensed upon grant. The Company grants options at exercise prices equal to the fair value of the Company’s common stock on the date of grant. The Company recorded stock-based compensation expense associated with stock option grants of $ 116,000 93,000 The Company uses the Black-Scholes option-pricing model to determine the fair value of options granted. The determination of the fair value of stock option awards on the date of grant using an option-pricing model is affected by the Company’s stock price as well as assumptions regarding a number of complex and subjective variables. These variables include expected stock price volatility over the term of the award, actual and projected employee stock option exercise behaviors, the risk-free interest rate and expected dividends. The Company used historical exercise, forfeiture, and post-vesting expiration data to estimate the expected term of options granted. The historical volatility of the Company’s common stock over a period of time equal to the expected term of the options granted was used to estimate expected volatility. The risk-free interest rate used in the option-pricing model was based on United States Treasury zero-coupon issues with remaining terms similar to the expected term of the options. The dividend yield assumption considers the expectation of continued declaration of dividends, offset by option holders’ dividend equivalent rights. The Company accounts for forfeitures of stock-based awards when they occur. All stock-based payment awards are recognized on a straight-line basis over the requisite service periods of the awards.

Treasury Stock

Treasury Stock	6 Months Ended
	Jun. 29, 2018
Equity [Abstract]
Treasury Stock	Note 6: Treasury Stock On October 21, 2015, the Company’s Board of Directors authorized the use of $ 35,000,000 35,000,000 The Company did not repurchase any shares of its common stock during the six months ended June 29, 2018. The Company repurchased 235,164 7,004,000 45,376,000 Net losses related to the re-issuance of treasury stock to settle restricted stock unit and stock option awards of $ 5,892,000 5,667,000

Deferred Compensation Plans

Deferred Compensation Plans	6 Months Ended
	Jun. 29, 2018
Deferred Compensation Arrangements [Abstract]
Deferred Compensation Plans	Note 7: Deferred Compensation Plans The Company maintains nonqualified deferred compensation plans for the benefit of a select group of highly compensated employees. Under these plans, participants may elect to defer up to 100 58,487,000 53,350,000 As of June 29, 2018 and December 29, 2017, vested amounts due under the plans totaled $ 62,196,000 59,050,000 1,020,000

Supplemental Cash Flow Informat

Supplemental Cash Flow Information	6 Months Ended
	Jun. 29, 2018
Supplemental Cash Flow Information [Abstract]
Supplemental Cash Flow Information	Note 8: Supplemental Cash Flow Information Six Months Ended (In thousands) June 29, 2018 June 30, 2017 Cash paid during period: Income taxes $ 12,217 $ 8,522 Non-cash investing and financing activities: Unrealized (loss) gain on short-term investments $ (21) $ 4 Vested stock unit awards issued to settle accrued bonuses $ 7,643 $ 6,910 Accrual for capital expenditures $ 691 $ 135

Accounts Receivable, Net

Accounts Receivable, Net	6 Months Ended
	Jun. 29, 2018
Receivables [Abstract]
Accounts Receivable, Net	Note 9: Accounts Receivable, Net June 29, December 29, (In thousands) 2018 2017 Billed accounts receivable $ 77,953 $ 78,139 Unbilled accounts receivable 42,223 35,487 Allowance for contract losses and doubtful accounts (3,644) (3,526) Total accounts receivable, net $ 116,532 $ 110,100

Segment Reporting

Segment Reporting	6 Months Ended
	Jun. 29, 2018
Segment Reporting [Abstract]
Segment Reporting	Note 10: Segment Reporting The Company has two reportable operating segments based on two primary areas of service. The Engineering and Other Scientific segment is a broad service group providing technical consulting in different practices primarily in engineering. The Environmental and Health segment provides services in the area of environmental, epidemiology and health risk analysis. This segment provides a wide range of consulting services relating to environmental hazards and risks and the impact on both human health and the environment. Our Chief Executive Officer, the chief operating decision maker, reviews revenues and operating income for each of our reportable segments but does not review total assets in evaluating segment performance and capital allocation. Segment information for the three and six months ended June 29, 2018 and July 30, 2017 follows: Three Months Ended Six Months Ended (In thousands) June 29, 2018 June 30, 2017 June 29, 2018 June 30, 2017 Engineering and Other Scientific $ 77,080 $ 69,795 $ 154,127 $ 136,478 Environmental and Health 18,541 18,045 37,951 35,484 Total revenues $ 95,621 $ 87,840 $ 192,078 $ 171,962 Operating Income Three Months Ended Six Months Ended (In thousands) June 29, 2018 June 30, 2017 June 29, 2018 June 30, 2017 Engineering and Other Scientific $ 25,802 $ 24,313 $ 51,715 $ 46,634 Environmental and Health 6,156 5,824 12,780 11,303 Total segment operating income 31,958 30,137 64,495 57,937 Corporate operating expense (9,480) (9,820) (20,419) (22,986) Total operating income $ 22,478 $ 20,317 $ 44,076 $ 34,951 Three Months Ended Six Months Ended (In thousands) June 29, 2018 June 30, 2017 June 29, 2018 June 30, 2017 Engineering and Other Scientific $ 1,291 $ 794 $ 2,104 $ 1,802 Environmental and Health 47 64 98 106 Total segment capital expenditures 1,338 858 2,202 1,908 Corporate capital expenditures 801 361 6,747 618 Total capital expenditures $ 2,139 $ 1,219 $ 8,949 $ 2,526 Depreciation and Amortization Three Months Ended Six Months Ended (In thousands) June 29, 2018 June 30, 2017 June 29, 2018 June 30, 2017 Engineering and Other Scientific $ 1,121 $ 1,163 $ 2,216 $ 2,278 Environmental and Health 41 44 80 85 Total segment depreciation and amortization 1,162 1,207 2,296 2,363 Corporate depreciation and amortization 432 422 853 832 Total depreciation and amortization $ 1,594 $ 1,629 $ 3,149 $ 3,195 One client comprised 12 14 10 12 10 18 24 10

Contingencies

Contingencies	6 Months Ended
	Jun. 29, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Note 11: Contingencies The Company is a party to various legal actions from time to time and may be contingently liable in connection with claims and contracts arising in the normal course of business, the outcome of which the Company believes, after consultation with legal counsel, will not have a material adverse effect on its financial condition, results of operations or liquidity. However, due to the risks and uncertainties inherent in legal proceedings, actual results could differ from current expected results. All legal costs associated with litigation are expensed as incurred.

Basis of Presentation (Policies

Basis of Presentation (Policies)	6 Months Ended
	Jun. 29, 2018
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation Exponent, Inc. (referred to as the “Company” or “Exponent”) is an engineering and scientific consulting firm that provides solutions to complex problems. The Company operates on a 52-53 week fiscal year ending on the Friday closest to the last day of December. The accompanying unaudited condensed consolidated financial statements are prepared in accordance with accounting principles generally accepted in the United States of America for interim financial information, the instructions to Form 10-Q and Article 10 of Regulation S-X promulgated by the Securities and Exchange Commission. Accordingly, they do not contain all the information and notes required by accounting principles generally accepted in the United States of America for complete financial statements. In the opinion of management, all adjustments which are necessary for the fair presentation of the condensed consolidated financial statements have been included and all such adjustments are of a normal and recurring nature. The operating results for the three and six months ended June 29, 2018 are not necessarily representative of the results of future quarterly or annual periods. The following information should be read in conjunction with the audited consolidated financial statements and accompanying notes thereto included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 29, 2017, which was filed with the U.S. Securities and Exchange Commission on February 23, 2018. The unaudited condensed consolidated financial statements include the accounts of Exponent, Inc. and its subsidiaries, which are all wholly owned. All intercompany accounts and transactions have been eliminated in consolidation.
Stock Split	Stock Split. 120,000,000
Dividend	Dividend. Fiscal Year 2018 Dividends Amount Per Share (in thousands) First Quarter $ 0.13 $ 6,700 Second Quarter 0.13 6,764 Total $ 0.26 $ 13,464 Fiscal Year 2017 Dividends Amount Per Share (in thousands) First Quarter $ 0.105 $ 5,374 Second Quarter 0.105 5,424 Third Quarter 0.105 5,424 Fourth Quarter 0.105 5,416 Total $ 0.420 $ 21,638 On July 19, 2018 0.13 September 21, 2018 September 7, 2018
Use of Estimates	Use of Estimates. The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions 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 revenues and expenses during the period. Items subject to such estimates and assumptions include accounting for revenue recognition and estimating the allowance for contract losses and doubtful accounts. Actual results could differ from those estimates.
Recently Adopted Accounting Pronouncements	Recently Adopted Accounting Pronouncements Revenue from Contracts with Customers Recent Accounting Pronouncements Not Yet Effective Leases

Basis of Presentation (Tables)

Basis of Presentation (Tables)	6 Months Ended
	Jun. 29, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Common Stock Dividends Declared Per Share	The Company declared and paid cash dividends per common share during the periods presented as follows: Fiscal Year 2018 Dividends Amount Per Share (in thousands) First Quarter $ 0.13 $ 6,700 Second Quarter 0.13 6,764 Total $ 0.26 $ 13,464 Fiscal Year 2017 Dividends Amount Per Share (in thousands) First Quarter $ 0.105 $ 5,374 Second Quarter 0.105 5,424 Third Quarter 0.105 5,424 Fourth Quarter 0.105 5,416 Total $ 0.420 $ 21,638

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 29, 2018
Fair Value Disclosures [Abstract]
Assets and Liabilities Measured at Fair Value on Recurring Basis	The fair value of these certain financial assets and liabilities was determined using the following inputs at June 29, 2018: Fair Value Measurements at Reporting Date Using (In thousands) Total Quoted Prices in Significant Other Significant Assets Money market securities (1) $ 6,267 $ 6,267 $ - $ - Fixed income available-for-sale securities (2) 75,534 - 75,534 - Fixed income trading securities held in deferred compensation plan (3) 16,419 16,419 - - Equity trading securities held in deferred compensation plan (3) 42,068 42,068 - - Total $ 140,288 $ 64,754 $ 75,534 $ - Liabilities Deferred compensation plan (4) 62,196 62,196 - - Total $ 62,196 $ 62,196 $ - $ - (1) Included in cash and cash equivalents on the Company’s unaudited condensed consolidated balance sheet. (2) Included in short-term investments on the Company’s unaudited condensed consolidated balance sheet. (3) Included in prepaid expenses and other assets and deferred compensation plan assets on the Company’s unaudited condensed consolidated balance sheet. (4) Included in accrued payroll and employee benefits and deferred compensation on the Company’s unaudited condensed consolidated balance sheet. The fair value of these certain financial assets and liabilities was determined using the following inputs at December 29, 2017: Fair Value Measurements at Reporting Date Using (In thousands) Total Quoted Prices in Significant Other Significant Assets Money market securities (1) $ 9,742 $ 9,742 $ - $ - Fixed income available- for-sale securities (2) 71,604 - 71,604 - Fixed income trading securities held in deferred compensation plan (3) 13,686 13,686 - - Equity trading securities held in deferred compensation plan (3) 39,664 39,664 - - Total $ 134,696 $ 63,092 $ 71,604 $ - Liabilities Deferred compensation plan (4) 59,050 59,050 - - Total $ 59,050 $ 59,050 $ - $ - (1) Included in cash and cash equivalents on the Company’s unaudited condensed consolidated balance sheet. (2) Included in short-term investments on the Company’s unaudited condensed consolidated balance sheet. (3) Included in prepaid expenses and other assets and deferred compensation plan assets on the Company’s unaudited condensed consolidated balance sheet. (4) Included in accrued payroll and employee benefits and deferred compensation on the Company’s unaudited condensed consolidated balance sheet.
Cash, cash equivalents and short-term investments	Cash, cash equivalents and short-term investments consisted of the following as of June 29, 2018: Amortized Unrealized Unrealized Estimated (In thousands) Cost Gains Losses Fair Value Classified as current assets: Cash $ 111,506 $ - $ - $ 111,506 Cash equivalents: Money market securities 6,267 - - 6,267 Total cash equivalents 6,267 - - 6,267 Total cash and cash equivalents 117,773 - - 117,773 Short-term investments: U.S. Treasury and agency securities 75,955 - (421) 75,534 Total short-term investments 75,955 - (421) 75,534 Total cash, cash equivalents and short-term investments $ 193,728 $ - $ (421) $ 193,307 Cash, cash equivalents and short-term investments consisted of the following as of December 29, 2017: Amortized Unrealized Unrealized Estimated (In thousands) Cost Gains Losses Fair Value Classified as current assets: Cash $ 115,052 $ - $ - $ 115,052 Cash equivalents: Money market securities 9,742 - - 9,742 Total cash equivalents 9,742 - - 9,742 Total cash and cash equivalents 124,794 - - 124,794 Short-term investments: U.S. Treasury and agency securities 71,997 - (393) 71,604 Total short-term investments 71,997 - (393) 71,604 Total cash, cash equivalents and short-term investments $ 196,791 $ - $ (393) $ 196,398
Summary of Cost and Estimated Fair Value of Short Term Fixed Income Securities	The following table summarizes the cost and estimated fair value of short-term fixed income securities classified as short-term investments based on stated effective maturities as of June 29, 2018: Amortized Estimated (In thousands) Cost Fair Value Due within one year $ 43,947 $ 43,784 Due between one and two years 32,008 31,750 Total $ 75,955 $ 75,534

Net Income Per Share (Tables)

Net Income Per Share (Tables)	6 Months Ended
	Jun. 29, 2018
Earnings Per Share [Abstract]
Reconciles Shares to Calculate Basic and Diluted Net Income Per Share	The following schedule reconciles the shares used to calculate basic and diluted net income per share: Three Months Ended Six Months Ended (In thousands) June 29, June 30, June 29, June 30, Shares used in basic per share computation 53,008 52,830 52,876 52,716 Effect of dilutive common stock options outstanding 398 270 362 266 Effect of dilutive restricted stock units outstanding 789 836 873 978 Shares used in diluted per share computation 54,195 53,936 54,111 53,960

Supplemental Cash Flow Inform22

Supplemental Cash Flow Information (Tables)	6 Months Ended
	Jun. 29, 2018
Supplemental Cash Flow Information [Abstract]
Supplemental Disclosure of Cash Flow Information	The following is supplemental disclosure of cash flow information: Six Months Ended (In thousands) June 29, 2018 June 30, 2017 Cash paid during period: Income taxes $ 12,217 $ 8,522 Non-cash investing and financing activities: Unrealized (loss) gain on short-term investments $ (21) $ 4 Vested stock unit awards issued to settle accrued bonuses $ 7,643 $ 6,910 Accrual for capital expenditures $ 691 $ 135

Accounts Receivable, Net (Table

Accounts Receivable, Net (Tables)	6 Months Ended
	Jun. 29, 2018
Receivables [Abstract]
Accounts Receivable, Net	At June 29, 2018 and December 29, 2017, accounts receivable, net, was comprised of the following: June 29, December 29, (In thousands) 2018 2017 Billed accounts receivable $ 77,953 $ 78,139 Unbilled accounts receivable 42,223 35,487 Allowance for contract losses and doubtful accounts (3,644) (3,526) Total accounts receivable, net $ 116,532 $ 110,100

Segment Reporting (Tables)

Segment Reporting (Tables)	6 Months Ended
	Jun. 29, 2018
Segment Reporting [Abstract]
Segment Reporting Information, by Segment	Segment information for the three and six months ended June 29, 2018 and July 30, 2017 follows: Three Months Ended Six Months Ended (In thousands) June 29, 2018 June 30, 2017 June 29, 2018 June 30, 2017 Engineering and Other Scientific $ 77,080 $ 69,795 $ 154,127 $ 136,478 Environmental and Health 18,541 18,045 37,951 35,484 Total revenues $ 95,621 $ 87,840 $ 192,078 $ 171,962 Operating Income Three Months Ended Six Months Ended (In thousands) June 29, 2018 June 30, 2017 June 29, 2018 June 30, 2017 Engineering and Other Scientific $ 25,802 $ 24,313 $ 51,715 $ 46,634 Environmental and Health 6,156 5,824 12,780 11,303 Total segment operating income 31,958 30,137 64,495 57,937 Corporate operating expense (9,480) (9,820) (20,419) (22,986) Total operating income $ 22,478 $ 20,317 $ 44,076 $ 34,951 Three Months Ended Six Months Ended (In thousands) June 29, 2018 June 30, 2017 June 29, 2018 June 30, 2017 Engineering and Other Scientific $ 1,291 $ 794 $ 2,104 $ 1,802 Environmental and Health 47 64 98 106 Total segment capital expenditures 1,338 858 2,202 1,908 Corporate capital expenditures 801 361 6,747 618 Total capital expenditures $ 2,139 $ 1,219 $ 8,949 $ 2,526 Depreciation and Amortization Three Months Ended Six Months Ended (In thousands) June 29, 2018 June 30, 2017 June 29, 2018 June 30, 2017 Engineering and Other Scientific $ 1,121 $ 1,163 $ 2,216 $ 2,278 Environmental and Health 41 44 80 85 Total segment depreciation and amortization 1,162 1,207 2,296 2,363 Corporate depreciation and amortization 432 422 853 832 Total depreciation and amortization $ 1,594 $ 1,629 $ 3,149 $ 3,195

Basis of Presentation - Additio

Basis of Presentation - Additional Information (Detail) - $ / shares shares in Thousands	1 Months Ended
	Jul. 19, 2018	Jun. 29, 2018	Dec. 29, 2017
Class of Stock [Line Items]
Common Stock Shares Authorized		120,000	120,000
Subsequent Event
Class of Stock [Line Items]
Common stock, dividends per share declared, subsequent event	$ 0.13
Dividends Payable, Date Declared	Jul. 19, 2018
Dividends Payable, Date to be Paid	Sep. 21, 2018
Dividends Payable, Date of Record	Sep. 7, 2018

Common Stock Dividends Declared

Common Stock Dividends Declared And Paid Per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended						6 Months Ended	12 Months Ended
	Jun. 29, 2018	Mar. 30, 2018	Dec. 29, 2017	Sep. 29, 2017	Jun. 30, 2017	Mar. 31, 2017	Jun. 29, 2018	Dec. 29, 2017
Class of Stock [Line Items]
Dividends Per Share	$ 0.13	$ 0.13	$ 0.105	$ 0.105	$ 0.105	$ 0.105	$ 0.26	$ 0.420
Amount	$ 6,764	$ 6,700	$ 5,416	$ 5,424	$ 5,424	$ 5,374	$ 13,464	$ 21,638

Revenue Recognition- Additional

Revenue Recognition- Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 29, 2018	Jun. 30, 2017	Jun. 29, 2018	Jun. 30, 2017
Revenues	$ 95,621,000	$ 87,840,000	$ 192,078,000	$ 171,962,000
Deferred Revenue, Revenue Recognized	2,671,000		4,604,000
Subcontractor Fees Not Included In Revenues	5,800,000		11,400,000
Engineering and Other Scientific [Member] | Time And Materials Contracts [Member]
Revenues	62,347,000		126,948,000
Engineering and Other Scientific [Member] | Fixed Price Contracts [Member]
Revenues	14,733,000		27,179,000
Environmental and Health [Member] | Time And Materials Contracts [Member]
Revenues	17,618,000		36,188,000
Environmental and Health [Member] | Fixed Price Contracts [Member]
Revenues	923,000		1,763,000
Sales Revenue, Net [Member] | Time And Materials Contracts [Member]
Revenues	$ 79,965,000		$ 163,136,000
Concentration Risk, Percentage	84.00%		85.00%
Sales Revenue, Net [Member] | Fixed Price Contracts [Member]
Revenues	$ 15,656,000		$ 28,942,000
Concentration Risk, Percentage	16.00%		15.00%

Assets and Liabilities Measured

Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands		Jun. 29, 2018	Dec. 29, 2017
Assets
Money market securities	[1]	$ 6,267	$ 9,742
Total		140,288	134,696
Liabilities
Deferred compensation plan	[2]	62,196	59,050
Total		62,196	59,050
Fixed income securities
Assets
Fixed income available-for-sale securities	[3]	75,534	71,604
Fixed income trading securities held in deferred compensation plan	[4]	16,419	13,686
Equity securities
Assets
Equity trading securities held in deferred compensation plan	[4]	42,068	39,664
Fair Value, Inputs, Level 1
Assets
Money market securities	[1]	6,267	9,742
Total		64,754	63,092
Liabilities
Deferred compensation plan	[2]	62,196	59,050
Total		62,196	59,050
Fair Value, Inputs, Level 1 | Fixed income securities
Assets
Fixed income available-for-sale securities	[3]	0	0
Fixed income trading securities held in deferred compensation plan	[4]	16,419	13,686
Fair Value, Inputs, Level 1 | Equity securities
Assets
Equity trading securities held in deferred compensation plan	[4]	42,068	39,664
Fair Value, Inputs, Level 2
Assets
Money market securities	[1]	0	0
Total		75,534	71,604
Liabilities
Deferred compensation plan	[2]	0	0
Total		0	0
Fair Value, Inputs, Level 2 | Fixed income securities
Assets
Fixed income available-for-sale securities	[3]	75,534	71,604
Fixed income trading securities held in deferred compensation plan	[4]	0	0
Fair Value, Inputs, Level 2 | Equity securities
Assets
Equity trading securities held in deferred compensation plan	[4]	0	0
Fair Value, Inputs, Level 3
Assets
Money market securities	[1]	0	0
Total		0	0
Liabilities
Deferred compensation plan	[2]	0	0
Total		0	0
Fair Value, Inputs, Level 3 | Fixed income securities
Assets
Fixed income available-for-sale securities	[3]	0	0
Fixed income trading securities held in deferred compensation plan	[4]	0	0
Fair Value, Inputs, Level 3 | Equity securities
Assets
Equity trading securities held in deferred compensation plan	[4]	$ 0	$ 0
[1]	Included in cash and cash equivalents on the Company’s unaudited condensed consolidated balance sheet.
[2]	Included in accrued payroll and employee benefits and deferred compensation on the Company’s unaudited condensed consolidated balance sheet.
[3]	Included in short-term investments on the Company’s unaudited condensed consolidated balance sheet.
[4]	Included in prepaid expenses and other assets and deferred compensation plan assets on the Company’s unaudited condensed consolidated balance sheet.

Cash, cash equivalents and shor

Cash, cash equivalents and short-term investments (Detail) - USD ($) $ in Thousands	Jun. 29, 2018	Dec. 29, 2017
Fair Value Measurements [Line Items]
Amortized Cost	$ 193,728	$ 196,791
Unrealized Gains	0	0
Unrealized Losses	(421)	(393)
Estimated Fair Value	193,307	196,398
U.S. Treasury and agency securities
Fair Value Measurements [Line Items]
Amortized Cost	75,955	71,997
Unrealized Gains	0	0
Unrealized Losses	(421)	(393)
Estimated Fair Value	75,534	71,604
Cash
Fair Value Measurements [Line Items]
Amortized Cost	111,506	115,052
Unrealized Gains	0	0
Unrealized Losses	0	0
Estimated Fair Value	111,506	115,052
Money market securities
Fair Value Measurements [Line Items]
Amortized Cost	6,267	9,742
Unrealized Gains	0	0
Unrealized Losses	0	0
Estimated Fair Value	6,267	9,742
Total cash equivalents
Fair Value Measurements [Line Items]
Amortized Cost	6,267	9,742
Unrealized Gains	0	0
Unrealized Losses	0	0
Estimated Fair Value	6,267	9,742
Total cash and cash equivalents
Fair Value Measurements [Line Items]
Amortized Cost	117,773	124,794
Unrealized Gains	0	0
Unrealized Losses	0	0
Estimated Fair Value	117,773	124,794
Total short-term investments
Fair Value Measurements [Line Items]
Amortized Cost	75,955	71,997
Unrealized Gains	0	0
Unrealized Losses	(421)	(393)
Estimated Fair Value	$ 75,534	$ 71,604

Summarizes Cost And Estimated F

Summarizes Cost And Estimated Fair Value Of Short Term Fixed Income Securities (Detail) - USD ($) $ in Thousands	Jun. 29, 2018	Dec. 29, 2017
Fair Value Measurements [Line Items]
Due within one year, Amortized Cost	$ 43,947
Due between one and two years, Amortized Cost	32,008
Total Amortized Cost	75,955
Due within one year, Estimated Fair Value	43,784
Due between one and two years, Estimated Fair Value	31,750
Total Estimated Fair Value	$ 75,534	$ 71,604

Reconciles the Denominators of

Reconciles the Denominators of the Company’s Calculation for Basic and Diluted Net Income per Share (Detail) - shares shares in Thousands	3 Months Ended		6 Months Ended
	Jun. 29, 2018	Jun. 30, 2017	Jun. 29, 2018	Jun. 30, 2017
Schedule Of Earnings Per Share Basic and Diluted [Line Items]
Shares used in basic per share computation	53,008	52,830	52,876	52,716
Shares used in diluted per share computation	54,195	53,936	54,111	53,960
Employee Stock Option
Schedule Of Earnings Per Share Basic and Diluted [Line Items]
Effect of dilutive stock outstanding	398	270	362	266
Restricted Stock Units (RSUs)
Schedule Of Earnings Per Share Basic and Diluted [Line Items]
Effect of dilutive stock outstanding	789	836	873	978

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 29, 2018	Jun. 30, 2017	Jun. 29, 2018	Jun. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based Compensation Arrangement By Share Based Payment Award Options Expiration Term			10 years
Unvested Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation, vesting period			4 years
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation expense	$ 116,000	$ 93,000	$ 4,129,000	$ 59
Vesting percentage of stock options granted per year			40.00%
Stock based compensation, vesting period			4 years
Vested Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation expense	2,168,000	2,201,000	$ 4,400,000	4,129,000
Stock based compensation, holding period			4 years
Vested Restricted Stock Awards | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of annual bonus settled with fully vested restricted stock unit awards			40.00%
Unvested Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation expense	$ 1,460,000	$ 1,238,000	$ 4,968,000	$ 4,494,000
Unvested Restricted Stock Awards | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recipient age to expense award on grant date			59 years 6 months
Unvested Stock Options | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recipient age to expense award on grant date			59 years 6 months

Treasury Stock - Additional Inf

Treasury Stock - Additional Information (Detail) - USD ($)	6 Months Ended
	Jun. 29, 2018	Jun. 30, 2017	Oct. 19, 2016	Oct. 21, 2015
Equity, Class of Treasury Stock [Line Items]
Stock Repurchase Program, Authorized Amount			$ 35,000,000	$ 35,000,000
Purchase of treasury shares (in shares)		235,164
Repurchase of treasury shares		$ 7,004,000
Remaining authorized amount for repurchase of common stock	$ 45,376,000
Treasury stock reissued at lower than repurchase price	$ 5,892,000	$ 5,667,000

Deferred Compensation Plans - A

Deferred Compensation Plans - Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 29, 2018	Jun. 30, 2017	Jun. 29, 2018	Jun. 30, 2017	Dec. 29, 2017
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Trading securities	$ 58,487,000		$ 58,487,000		$ 53,350,000
Deferred compensation plan vested amounts due	62,196,000		62,196,000		$ 59,050,000
Change in market value of trust assets	$ 1,043,000	$ 1,020,000	$ 737,000	$ 2,917,000
Maximum
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Percentage of compensation deferred			100.00%

Supplemental Disclosure of Cash

Supplemental Disclosure of Cash Flow Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 29, 2018	Jun. 30, 2017	Jun. 29, 2018	Jun. 30, 2017
Cash paid during period:
Income taxes			$ 12,217	$ 8,522
Non-cash investing and financing activities:
Unrealized (loss) gain on short-term investments	$ 19	$ (32)	(21)	4
Vested stock unit awards issued to settle accrued bonuses			7,643	6,910
Accrual for capital expenditures			$ 691	$ 135

Accounts Receivable, Net (Detai

Accounts Receivable, Net (Detail) - USD ($) $ in Thousands	Jun. 29, 2018	Dec. 29, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for contract losses and doubtful accounts	$ (3,644)	$ (3,526)
Total accounts receivable, net	116,532	110,100
Billed accounts receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts Receivable	77,953	78,139
Unbilled accounts receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts Receivable	$ 42,223	$ 35,487

Segment Reporting - Additional

Segment Reporting - Additional Information (Detail)	3 Months Ended		6 Months Ended
	Jun. 29, 2018	Jun. 30, 2017	Jun. 29, 2018	Jun. 30, 2017	Dec. 29, 2017
Segment Reporting Information [Line Items]
Percentage of Company's revenue	10.00%	10.00%	10.00%	10.00%
Sales Revenue, Net [Member] | Customer Concentration Risk [Member]
Segment Reporting Information [Line Items]
Concentration Risk, Percentage	12.00%		14.00%	12.00%
Accounts Receivable [Member]
Segment Reporting Information [Line Items]
Percentage of account receivable	10.00%		10.00%
Accounts Receivable [Member] | Customer Concentration Risk [Member]
Segment Reporting Information [Line Items]
Percentage of account receivable	18.00%		18.00%		24.00%

Segment Reporting (Detail)

Segment Reporting (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 29, 2018	Jun. 30, 2017	Jun. 29, 2018	Jun. 30, 2017
Segment Reporting Information [Line Items]
Revenues	$ 95,621	$ 87,840	$ 192,078	$ 171,962
Operating Income	22,478	20,317	44,076	34,951
Capital Expenditures	2,139	1,219	8,949	2,526
Depreciation and Amortization	1,594	1,629	3,149	3,195
Operating segments
Segment Reporting Information [Line Items]
Operating Income	31,958	30,137	64,495	57,937
Capital Expenditures	1,338	858	2,202	1,908
Depreciation and Amortization	1,162	1,207	2,296	2,363
Engineering and Other Scientific
Segment Reporting Information [Line Items]
Revenues	77,080	69,795	154,127	136,478
Operating Income	25,802	24,313	51,715	46,634
Capital Expenditures	1,291	794	2,104	1,802
Depreciation and Amortization	1,121	1,163	2,216	2,278
Environmental and Health
Segment Reporting Information [Line Items]
Revenues	18,541	18,045	37,951	35,484
Operating Income	6,156	5,824	12,780	11,303
Capital Expenditures	47	64	98	106
Depreciation and Amortization	41	44	80	85
Corporate
Segment Reporting Information [Line Items]
Operating Income	(9,480)	(9,820)	(20,419)	(22,986)
Capital Expenditures	801	361	6,747	618
Depreciation and Amortization	$ 432	$ 422	$ 853	$ 832