NV5 Global (NVEE) 10-K 26 Feb 20 2019 FY Annual report Financial data

Cover Page

Cover Page - USD ($) $ in Millions	12 Months Ended
	Dec. 28, 2019	Feb. 19, 2020	Jun. 29, 2019
Cover page.
Document Type	10-K
Document Annual Report	true
Document Transition Report	false
Document Period End Date	Dec. 28, 2019
Entity File Number	001-35849
Entity Registrant Name	NV5 Global, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	45-3458017
Entity Address, Address Line One	200 South Park Road,
Entity Address, Address Line Two	Suite 350,
Entity Address, City or Town	Hollywood,
Entity Address, State or Province	FL
Entity Address, Postal Zip Code	33021
City Area Code	954
Local Phone Number	495-2112
Title of 12(b) Security	Common Stock, $0.01 par value
Trading Symbol	NVEE
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Public Float			$ 838.6
Entity Common Stock, Shares Outstanding		12,893,660
Documents Incorporated by Reference	DOCUMENTS INCORPORATED BY REFERENCE Portions of the 2020 definitive Proxy Statement are incorporated by reference into Part III of this Form 10-K.
Entity Central Index Key	0001532961
Current Fiscal Year End Date	--12-28
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
Amendment Flag	false

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018
Current assets:
Cash and cash equivalents	$ 31,825	$ 40,739
Billed receivables, net	131,041	98,324
Unbilled receivables, net	79,428	43,411
Prepaid expenses and other current assets	8,906	2,582
Total current assets	251,200	185,056
Property and equipment, net	25,733	11,677
Right-of-use lease assets, net	46,313	0
Intangible assets, net	255,961	99,756
Goodwill	309,216	140,930
Other assets	4,714	2,002
Total Assets	893,137	439,421
Current liabilities:
Accounts payable	36,116	22,588
Accrued liabilities	47,432	20,853
Income taxes payable	0	2,697
Billings in excess of costs and estimated earnings on uncompleted contracts	3,303	7,625
Client deposits	221	208
Current portion of contingent consideration	1,954	1,845
Current portion of notes payable and other obligations	25,332	17,139
Total current liabilities	114,358	72,955
Contingent consideration, less current portion	2,048	2,853
Long-term lease liabilities	34,573	0
Notes payable and other obligations, less current portion	332,854	29,847
Deferred income tax liabilities, net	53,341	16,224
Total liabilities	537,174	121,879
Commitments and contingencies
Stockholders’ equity:
Preferred stock, $0.01 par value; 5,000,000 shares authorized, no shares issued and outstanding	0	0
Common stock, $0.01 par value; 45,000,000 shares authorized, 12,852,357 and 12,550,711 shares issued and outstanding as of December 28, 2019 and December 29, 2018, respectively	129	126
Additional paid-in capital	251,187	236,525
Retained earnings	104,647	80,891
Total stockholders’ equity	355,963	317,542
Total liabilities and stockholders’ equity	$ 893,137	$ 439,421

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parentheticals) - $ / shares	Dec. 28, 2019	Dec. 29, 2018
Statement of Financial Position [Abstract]
Preferred Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Preferred Stock, Shares Authorized	5,000,000	5,000,000
Preferred Stock, Shares Issued	0	0
Preferred Stock, Shares Outstanding	0	0
Common Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Common Stock, Shares Authorized	45,000,000	45,000,000
Common Stock, Shares, Issued	12,852,357	12,550,711
Common Stock, Shares, Outstanding	12,852,357	12,550,711

Consolidated Statements of Net

Consolidated Statements of Net Income and Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Lessee, Lease, Description [Line Items]
Gross revenues	$ 508,938	$ 418,081	$ 333,034
Direct costs (excluding depreciation and amortization):
Salaries and wages	153,023	132,922	103,011
Sub-consultant services	79,598	62,218	50,171
Other direct costs	30,935	21,537	14,598
Total direct costs	263,556	216,677	167,780
Gross Profit	245,382	201,404	165,254
Operating Expenses:
Salaries and wages, payroll taxes and benefits	128,558	102,221	86,222
General and administrative	42,656	31,713	26,747
Facilities and facilities related	17,145	14,401	12,589
Depreciation and amortization	25,816	17,384	13,128
Total operating expenses	214,175	165,719	138,686
Income from operations	31,207	35,685	26,568
Interest expense	(2,275)	(1,966)	(1,935)
Income before income tax expense	28,932	33,719	24,633
Income tax expense	(5,176)	(6,863)	(627)
Net Income and Comprehensive Income	$ 23,756	$ 26,856	$ 24,006
Earnings per share:
Basic (USD per Share)	$ 1.96	$ 2.44	$ 2.36
Diluted (USD per Share)	$ 1.90	$ 2.33	$ 2.23
Weighted average common shares outstanding:
Basic (in shares)	12,116,185	10,991,124	10,178,901
Diluted (in shares)	12,513,034	11,506,466	10,777,806

Consolidated Statements of Chan

Consolidated Statements of Changes in Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Retained Earnings
Balance (in shares) at Dec. 31, 2016		10,566,528
Balance at Dec. 31, 2016	$ 148,161	$ 106	$ 118,026	$ 30,029
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock compensation	4,011		4,011
Restricted stock issuance, net (in shares)		176,198
Restricted stock issuance, net	0	$ 2	(2)
Stock issuance for acquisitions (in shares)		90,324
Stock issuance for acquisitions	3,856	$ 0	3,856
Payment of contingent consideration with common stock (in shares)		1,720
Payment of contingent consideration with common stock	63	$ 0	63
Net income	24,006	$ 0	0	24,006
Balance (in shares) at Dec. 30, 2017		10,834,770
Balance at Dec. 30, 2017	180,097	$ 108	125,954	54,035
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock compensation	6,697		6,697
Restricted stock issuance, net (in shares)		172,820
Restricted stock issuance, net	0	$ 2	(2)
Stock issuance for acquisitions (in shares)		133,121
Stock issuance for acquisitions	9,330	$ 1	9,329
Proceeds from secondary offering, net of costs (in shares)		1,270,000
Proceeds from secondary offering, net of costs	93,469	$ 13	93,456
Proceeds from exercise of warrants, net of costs (in shares)		140,000
Proceeds from exercise of warrants, net of costs	1,093	$ 2	1,091	0
Net income	26,856	$ 0	0	26,856
Balance (in shares) at Dec. 29, 2018		12,550,711
Balance at Dec. 29, 2018	317,542	$ 126	236,525	80,891
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock compensation	10,430		10,430
Restricted stock issuance, net (in shares)		234,805
Restricted stock issuance, net	0	$ 2	(2)
Stock issuance for acquisitions (in shares)		55,656
Stock issuance for acquisitions	3,511	$ 1	3,510
Payment of contingent consideration with common stock (in shares)		11,185
Payment of contingent consideration with common stock	724	$ 0	724
Net income	23,756	$ 0	0	23,756
Balance (in shares) at Dec. 28, 2019		12,852,357
Balance at Dec. 28, 2019	$ 355,963	$ 129	$ 251,187	$ 104,647

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Cash Flows From Operating Activities:
Net income	$ 23,756	$ 26,856	$ 24,006
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	25,816	17,384	13,128
Non-cash lease expense	9,410	0	0
Provision for doubtful accounts	1,239	797	586
Stock based compensation	10,430	6,697	4,011
Change in fair value of contingent consideration	(216)	424	(832)
Loss on disposals of property and equipment	21	26	35
Deferred income taxes	(6,634)	(3,585)	(11,242)
Amortization of debt issuance costs	131	0	0
Changes in operating assets and liabilities, net of impact of acquisitions:
Billed receivables	5,140	(8,662)	(10,911)
Unbilled receivables	(11,807)	(2,813)	(3,802)
Prepaid expenses and other assets	(3,599)	(109)	295
Accounts payable	534	398	(1,495)
Accrued liabilities	(7,315)	(2,984)	(2,442)
Income taxes payable	(2,697)	(3,405)	4,969
Billings in excess of costs and estimated earnings on uncompleted contracts	(4,322)	3,964	436
Deposits	13	11	883
Net cash provided by operating activities	39,900	34,999	17,625
Cash Flows From Investing Activities:
Cash paid for acquisitions (net of cash received from acquisitions)	(348,375)	(58,155)	(60,633)
Purchase of property and equipment	(2,625)	(2,203)	(2,239)
Net cash used in investing activities	(351,000)	(60,358)	(62,872)
Cash Flows From Financing Activities:
Proceeds from common stock offering	0	100,330	0
Proceeds from borrowings from Senior Credit Facility	330,457	0	47,000
Payments of borrowings from Senior Credit Facility	(10,000)	(36,500)	(10,500)
Payments on notes payable	(13,393)	(9,741)	(7,605)
Proceeds from exercise of warrant	0	1,093	0
Payments of contingent consideration	(1,202)	(728)	(563)
Payments of common stock offering costs	0	(6,861)	0
Payments of debt issuance costs	(3,676)	(246)	0
Net cash provided by financing activities	302,186	47,347	28,332
Net (decrease) increase in Cash and Cash Equivalents	(8,914)	21,988	(16,915)
Cash and cash equivalents – beginning of period	40,739	18,751	35,666
Cash and cash equivalents – end of period	31,825	40,739	18,751
Supplemental disclosures of cash flow information:
Cash paid for interest	1,218	1,895	1,508
Cash paid for income taxes	16,215	13,634	7,607
Contingent Consideration Earn-Out, Non-Cash	1,641	3,112	908
Non-cash investing and financing activities:
Notes payable and other obligations issued for acquisitions	10,044	23,987	9,371
Stock issuance for acquisitions	3,511	9,330	3,856
Stock issuance for acquisitions		9,330	3,856
Finance leases	1,084	2,884	0
Payment of contingent consideration with common stock	$ 724		63
Payment of contingent consideration and other obligations with common stock		$ 0	$ 63

Organization and Nature of Busi

Organization and Nature of Business Operations	12 Months Ended
	Dec. 28, 2019
Accounting Policies [Abstract]
Organization and Nature of Business Operations	Organization and Nature of Business Operations Business NV5 Global, Inc. and its subsidiaries (collectively, the “Company” or “NV5 Global”) is a provider of professional and technical engineering and consulting solutions to public and private sector clients in the infrastructure, energy, construction, real estate and environmental markets, operating nationwide and abroad. The Company’s clients include the U.S. federal, state and local governments, and the private sector. NV5 Global provides a wide range of services, including, but not limited to: ● Infrastructure, engineering and support ● Management oversight ● Construction quality assurance, testing and inspection ● Permitting ● Program management ● Inspection and field supervision ● Energy ● Testing inspection and certification ● Environmental ● Forensic engineering ● Planning ● Litigation support ● Design ● Condition assessment ● Consulting ● Compliance certification ● Geospatial solutions

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 28, 2019
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Basis of Presentation and Principles of Consolidation The consolidated financial statements of the Company are presented in U.S. dollars in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”) and have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”). The consolidated financial statements include the accounts of the Company and its subsidiaries. All intercompany transactions and balances have been eliminated in consolidation. Fiscal Year Effective March 7, 2017, the Audit Committee of our Board of Directors and the Board of Directors approved a change in our fiscal year-end and financial accounting cycle. Beginning January 1, 2017, the Company commenced reporting its financial results on a 52/53 week fiscal year ending on the Saturday closest to December 31st (whether or not in the following calendar year), with interim calendar quarters ending on the Saturday closest to the end of such calendar quarter (whether or not in the following calendar quarter). Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts in the consolidated financial statements and accompanying notes. These estimates and assumptions are based on management’s most recent assessment of underlying facts and circumstances using the most recent information available. Actual results could differ significantly from these estimates and assumptions, and the differences could be material. Estimates and assumptions are evaluated periodically and adjusted when necessary. The more significant estimates affecting amounts reported in the consolidated financial statements include the following: • Fair value estimates used in accounting for business combinations including the valuation of identifiable intangible assets and contingent consideration • Fair value estimates in determining the fair value of our reporting units for goodwill impairment assessment • Revenue recognition over time • Allowances for uncollectible accounts Cash and Cash Equivalents Cash and cash equivalents include cash on deposit with financial institutions and investments in high quality overnight money market funds, all of which have maturities of three months or less when purchased. The Company from time to time may be exposed to credit risk with its bank deposits in excess of the Federal Deposit Insurance Corporation insurance limits and with uninsured money market investments. Management believes cash and cash equivalent balances are not exposed to significant credit risk due to the financial position of the depository institutions in which those deposits are held. Concentration of Credit Risk Trade receivable balances carried by the Company are comprised of accounts from a diverse client base across a broad range of industries and are not collateralized. However, 27% , 30% and 32% of the Company’s gross revenues for fiscal years 2019, 2018 and 2017, respectively, are from California-based projects. The Company did not have any clients representing more than 10% of our gross revenues during 2019, 2018 or 2017. During fiscal years 2019, 2018 and 2017 approximately 68% , 67% and 68% , respectively, of our gross revenues was attributable to the public and quasi-public sector. Management continually evaluates the creditworthiness of these and future clients and provides for bad debt reserves as necessary. Fair Value of Financial Instruments Fair value is defined as the amount that would be received for selling an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date and is measured using inputs in one of the following three categories: Level 1 measurements are based on unadjusted quoted prices in active markets for identical assets or liabilities that we have the ability to access. Valuation of these items does not entail a significant amount of judgment. Level 2 measurements are based on quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active or market data other than quoted prices that are observable for the assets or liabilities. Level 3 measurements are based on unobservable data that are supported by little or no market activity and are significant to the fair value of the assets or liabilities. The Company considers cash and cash equivalents, accounts receivable, accounts payable, income taxes payable, accrued liabilities and debt obligations to meet the definition of financial instruments. As of December 28, 2019 and December 29, 2018 , the carrying amount of cash and cash equivalents, accounts receivable, accounts payable, income taxes payable and accrued liabilities approximate their fair value due to the relatively short period of time between their origination and their expected realization or payment. The carrying amounts of debt obligations approximate their fair values as the terms are comparable to terms currently offered by local lending institutions for arrangements with similar terms to industry peers with comparable credit characteristics. The Company applies the provisions of the Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) 805, Business Combinations , in the accounting for its acquisitions, which requires recognition of the assets acquired and the liabilities assumed at their acquisition date fair values, separately from goodwill. Goodwill as of the acquisition date is measured as the excess of consideration transferred and the net of the acquisition date fair values of the tangible and identifiable intangible assets acquired and liabilities assumed. The allocation of the purchase price to identifiable intangible assets is based on valuations performed to determine the fair values of such assets as of the acquisition dates. Generally, the Company engages a third-party independent valuation specialist to assist in management’s determination of fair values of tangible and intangible assets acquired and liabilities assumed. The fair values of earn-out arrangements are included as part of the purchase price of the acquired companies on their respective acquisition dates. The Company estimates the fair value of contingent earn-out payments as part of the initial purchase price and records the estimated fair value of contingent consideration as a liability on the consolidated balance sheet. Changes in the estimated fair value of contingent earn-out payments are included in General and Administrative expenses on the Consolidated Statements of Net Income and Comprehensive Income. Several factors are considered when determining contingent consideration liabilities as part of the purchase price, including whether (i) the valuation of the acquisitions is not supported solely by the initial consideration paid, and the contingent earn-out formula is a critical and material component of the valuation approach to determining the purchase price; and (ii) the former owners of the acquired companies that remain as key employees receive compensation other than contingent earn-out payments at a reasonable level compared with the compensation of other key employees. The contingent earn-out payments are not affected by employment termination. The Company reviews and re-assesses the estimated fair value of contingent consideration liabilities on a quarterly basis, and the updated fair value could differ from the initial estimates. The Company measures contingent consideration recognized in connection with business combinations at fair value on a recurring basis using significant unobservable inputs classified as Level 3 inputs. The Company uses a probability-weighted discounted cash flow approach as a valuation technique to determine the fair value of the contingent consideration liabilities on the acquisition date and at each reporting period. The significant unobservable inputs used in the fair value measurements are projections over the earn-out period, and the probability outcome percentages that are assigned to each scenario. Significant increases or decreases to either of these inputs in isolation could result in a significantly higher or lower liability with a higher liability capped by the contractual maximum of the contingent consideration liabilities. Ultimately, the liability will be equivalent to the amount paid, and the difference between the fair value estimate on the acquisition date and amount paid will be recorded in earnings. See Note 12, Contingent Consideration , for additional information regarding contingent considerations. Property and Equipment Property and equipment is stated at cost. Property and equipment acquired in a business combination is stated at fair value at the acquisition date. The Company capitalizes the cost of improvements to property and equipment that increase the value or extend the useful lives of the assets. Normal repair and maintenance costs are expensed as incurred. Depreciation and amortization is computed on a straight-line basis over the following estimated useful lives of the assets. Leasehold improvements are amortized on a straight-line basis over the lesser of their estimated useful lives or the remaining terms of the related lease agreement. Asset Depreciation Period (in years) Office furniture and equipment 4 Computer equipment 3 Survey and field equipment 5 Leasehold improvements Lesser of the estimated useful lives or remaining term of the lease Property and equipment balances are periodically reviewed by management for impairment whenever events or changes in circumstances indicate that the carrying value of the asset may not be recoverable. If an indicator of impairment exists, the Company compares the estimated future cash flows of the asset, on an undiscounted basis, to the carrying value of the asset. If the undiscounted cash flows exceed the carrying value, no impairment is indicated. If the undiscounted cash flows do not exceed the carrying value, then impairment is measured as the difference between fair value and carrying value, with fair value typically based on a discounted cash flow model. During fiscal years 2019 , 2018 and 2017 , no impairment charge relating to property and equipment was recognized. Goodwill and Intangible Assets Goodwill is the excess of consideration paid for an acquired entity over the amounts assigned to assets acquired, including other identifiable intangible assets and liabilities assumed in a business combination. To determine the amount of goodwill resulting from a business combination, we perform an assessment to determine the acquisition date fair value of the acquired company’s tangible and identifiable intangible assets and liabilities. The Company evaluates goodwill annually for impairment on August 1 or whenever events or changes in circumstances indicate the asset may be impaired. An entity has the option to first assess qualitative factors to determine whether the existence of events or circumstances leads to a determination that it is more likely than not that the fair value of a reporting unit is less than its carrying amount. These qualitative factors include: macroeconomic and industry conditions, cost factors, overall financial performance and other relevant entity-specific events. If the entity determines that this threshold is met, then performing the two-step quantitative impairment test is unnecessary. The two-step impairment test requires a comparison of the carrying value of the assets and liabilities associated with a reporting unit, including goodwill, with the fair value of the reporting unit. The Company determines fair value through multiple valuation techniques, and weights the results accordingly. NV5 Global is required to make certain subjective and complex judgments in assessing whether an event of impairment of goodwill has occurred, including assumptions and estimates used to determine the fair value of its reporting units. If the carrying value of its reporting unit exceeds the fair value of its reporting unit, the Company would calculate the implied fair value as compared to the carrying value to determine the appropriate impairment charge, if any. Identifiable intangible assets primarily include customer backlog, customer relationships, finite and indefinite-lived trade names, non-compete agreements, and developed technology. Amortizable intangible assets are amortized on a straight-line basis over their estimated useful lives and reviewed for impairment whenever events or changes in circumstances indicate that the assets may be impaired. If an indicator of impairment exists, the Company compares the estimated future cash flows of the asset, on an undiscounted basis, to the carrying value of the asset. If the undiscounted cash flows exceed the carrying value, no impairment is indicated. If the undiscounted cash flows do not exceed the carrying value, then impairment, if any, is measured as the difference between fair value and carrying value, with fair value typically based on a discounted cash flow model. During fiscal years 2019 , 2018 and 2017 , no impairment charge relating to goodwill and intangible assets was recognized. See Note 9, Goodwill and Intangible Assets , for further information on goodwill and identified intangibles. Revenue Recognition On the first day of fiscal year 2018, we adopted ASC Topic 606, Revenue from Contracts with Customers (“Topic 606”), using the modified retrospective approach to all contracts that were not completed as of the beginning of fiscal year 2018. We utilize the contract method, which allows companies to account for contracts on a contract by contract basis. For our time and materials contracts, we apply the as-invoiced practical expedient, which permits us to recognize revenue as the right to invoice for services performed. The new standard did not materially affect our consolidated net income, financial position, or cash flows. To determine the proper revenue recognition method, we evaluate whether two or more contracts should be combined and accounted for as one single contract and whether the combined or single contract should be accounted for as more than one performance obligation. The majority of our contracts have a single performance obligation as the promise to transfer the individual goods or services is not separately identifiable from other promises in the contracts and, therefore, is not distinct. The Company’s performance obligations are satisfied as work progresses or at a point in time. Revenue on our cost-reimbursable contracts is recognized over time using direct costs incurred or direct costs incurred to date as compared to the estimated total direct costs for performance obligations because it depicts the transfer of control to the customer. Contract costs include labor, subcontractors’ costs and other direct costs. Gross revenues from services transferred to customers over time accounted for 90% of the Company’s revenues for the period ended December 28, 2019 . Gross revenue from services transferred to customers at a point in time is recognized when the customer obtains control of the asset, which is generally upon delivery and acceptance by the customer of the reports and/or analysis performed. Gross revenue from services transferred to customers at a point in time accounted for 10% and 8% of the Company’s revenues for the period ended December 28, 2019 and December 29, 2018, respectively. As of December 28, 2019 , the Company had $607,482 of remaining performance obligations, of which 493,468 is expected to be recognized over the next 12 months and the majority of the balance over the next 24 months. Contracts for which work authorizations have been received are included in performance obligations. Most of our government contracts are multi-year contracts for which funding is appropriated on an annual basis, therefore performance obligations include only those amounts that have been funded and authorized and does not reflect the full amounts we may receive over the term of such contracts. In the case of non-government contracts and project awards, performance obligations include future revenue at contract or customary rates, excluding contract renewals or extensions that are at the discretion of the client. For contracts with a not-to-exceed maximum amount, we include revenue from such contracts in performance obligations to the extent of the remaining estimated amount. Contract modifications are common in the performance of our contracts. Contracts modified typically result from changes in scope, specifications, design, performance, sites, or period of completion. In most cases, contract modifications are for services that are not distinct, and, therefore, are accounted for as part of the existing contract. Contract estimates are based on various assumptions to project the outcome of future events. These assumptions are dependent upon the accuracy of a variety of estimates, including engineering progress, achievement of milestones, labor productivity and cost estimates. Due to uncertainties inherent in the estimation process, it is possible that actual completion costs may vary from estimates. If estimated total costs on contracts indicate a loss or reduction to the percentage of total contract revenues recognized to date, these losses or reductions are recognized in the period in which the revisions are known. The effect of revisions to revenues, estimated costs to complete contracts, including penalties, incentive awards, change orders, claims, anticipated losses and others are recorded on the cumulative catch-up basis in the period in which the revisions are identified and the loss can be reasonably estimated. Such revisions could occur in any reporting period and the effects on the results of operations for that reporting period may be material depending on the size of the project or the adjustment. During the period ended December 28, 2019 , the cumulative catch-up adjustment for contract modifications was not material. A significant amount of the Company’s revenues are derived under multi-year contracts. The Company enters into contracts with its clients that contain two principal types of pricing provisions: cost-reimbursable and fixed-unit price. The majority of the Company’s contracts are cost-reimbursable contracts that fall under the low-risk subcategory of time and materials contracts. Cost-reimbursable contracts consist of the following: • Time and materials contracts, which are common for smaller scale professional and technical consulting and certification services projects. Under these types of contracts, there is no predetermined fee. Instead, the Company negotiates hourly billing rates and charges the clients based upon actual hours expended on a project. In addition, any direct project expenditures are passed through to the client and are typically reimbursed. These contracts may have an initial not-to-exceed or guaranteed maximum price provision. • Cost-plus contracts are the predominant contracting method used by U.S. federal, state, and local governments. Under these types of contracts, the Company charges clients for its costs, including both direct and indirect costs, plus a negotiated fee. The total estimated cost plus the negotiated fee represents the total contract value. • Lump-sum contracts typically require the performance of all of the work under the contract for a specified lump-sum fee, subject to price adjustments if the scope of the project changes or unforeseen conditions arise. Many of the Company’s lump-sum contracts are negotiated and arise in the design of projects with a specified scope and project deliverables. In most cases, we can bill additional fees if the construction schedule is modified and lengthened. Fixed-unit price contracts typically require the performance of an estimated number of units of work at an agreed price per unit, with the total payment under the contract determined by the actual number of units performed. Federal Acquisition Regulations (“FAR”), which are applicable to the Company’s federal government contracts and may be incorporated in local and state agency contracts, limit the recovery of certain specified indirect costs on contracts. Cost-plus contracts covered by FAR or certain state and local agencies also may require an audit of actual costs and provide for upward or downward adjustments if actual recoverable costs differ from billed recoverable costs. Contract Balances The timing of revenue recognition, billings and cash collections results in billed receivables, unbilled receivables (contract assets), and billings in excess of costs and estimated earnings on uncompleted contracts (contract liabilities) on the Consolidated Balance Sheet. Billed receivables, net represents amounts billed to clients that remain uncollected as of the balance sheet date. The amounts are stated at their estimated realizable value. The Company maintains an allowance for doubtful accounts to provide for the estimated amount of receivables that will not be collected. The allowance is estimated based on management’s evaluation of the contracts involved and the financial condition of clients. Factors the Company considers include, but are not limited to: • Client type (governmental or commercial client) • Historical performance • Historical collection trends • General economic conditions Billed receivables are generally collected within less than 12 months. The allowance is increased by the Company’s provision for doubtful accounts which is charged against income. All recoveries on receivables previously charged off are included in income, while direct charge-offs of receivables are deducted from the allowance. Unbilled receivables, net represents recognized amounts pending billing pursuant to contract terms or accounts billed after period end, and are expected to be billed and collected within the next 12 months. Generally, billing occurs subsequent to revenue recognition, resulting in contract assets. Unbilled receivables (contract assets) are generally classified as current. In certain circumstances, the contract may allow for billing terms that result in the cumulative amounts billed in excess of revenues recognized. The liability “Billings in excess of costs and estimated earnings on uncompleted contracts” represents billings in excess of revenues recognized on these contracts as of the reporting date. This liability is generally classified as current. During fiscal 2019 , the Company performed services and recognized $7,625 of revenue related to its contract liabilities that existed as of December 29, 2018 . Advertising Advertising costs are charged to expense in the period incurred and amounted to $939 , $1,019 and $1,048 during fiscal years 2019 , 2018 and 2017 , respectively, which is included in General and Administrative Expenses on the accompanying Consolidated Statements of Net Income and Comprehensive Income. Income Taxes The Company accounts for income taxes in accordance with ASC Topic No. 740 “ Income Taxes ” (“Topic No. 740”). Deferred income taxes reflect the impact of temporary differences between amounts of assets and liabilities for financial reporting purposes and such amounts as measured by tax laws. A valuation allowance against the Company’s deferred tax assets is recorded when it is more likely than not that some portion or all of the deferred tax assets will not be realized. In determining the need for a valuation allowance, management is required to make assumptions and to apply judgment, including forecasting future earnings, taxable income, and the mix of earnings in the jurisdictions in which the Company operates. Management periodically assesses the need for a valuation allowance based on the Company’s current and anticipated results of operations. The need for and the amount of a valuation allowance can change in the near term if operating results and projections change significantly. The Company recognizes the consolidated financial statement benefit of a tax position only after determining that the relevant tax authority would more likely than not sustain the position following an audit. For tax positions meeting the more likely-than-not threshold, the amount recognized in the consolidated financial statements is the largest benefit that has a greater than 50 percent likelihood of being realized upon ultimate settlement with the relevant tax authority. The Company applies the uncertain tax position guidance to all tax positions for which the statute of limitations remains open. The Company’s policy is to classify interest and penalties as income tax expense.

Recent Issued Accounting Pronou

Recent Issued Accounting Pronouncements	12 Months Ended
	Dec. 28, 2019
Accounting Policies [Abstract]
Recently Issued Accounting Pronouncements	Recently Issued Accounting Pronouncements Recently Adopted Accounting Pronouncements Leases In February 2016, the FASB issued Accounting Standards Update ("ASU") No. 2016-02, Leases (Topic 842) ("ASU 2016-02") which is intended to increase transparency and comparability of accounting for lease transactions. For all leases with terms greater than 12 months, the new guidance requires lessees to recognize right-of-use assets and corresponding lease liabilities on the balance sheet and to disclose qualitative and quantitative information about lease transactions. The new standard maintains a distinction between finance leases and operating leases. As a result, the effect of the new guidance on leases in the statement of operations and statement of cash flow is largely unchanged. The Company adopted ASU No. 2016-02 as of the first day of the fiscal year 2019 using the modified retrospective approach and elected not to adjust comparative periods. In addition, the Company elected the package of practical expedients permitted under the transition guidance within the new standard, which permits the Company not to reassess under the new standard its prior conclusions about lease identification, lease classification, and the initial direct costs. The Company elected the practical expedient to keep leases with an initial term of 12 months or less off the balance sheet and the practical expedient to account for non-lease components in a contract as part of a single lease component. Lease payments are recognized in the Consolidated Statements of Operations on a straight-line basis over the lease term. Adoption of the new standard resulted in the recording of additional right-of-use lease assets and lease liabilities of $34,186 and $34,965 , respectively, as of the first day of the fiscal year 2019. The standard did not materially impact our consolidated net earnings and had no impact on cash flows. Additionally, there was no cumulative effect of adoption on retained earnings in the Statement of Changes in Stockholders' Equity. Accounting Pronouncements Not Yet Adopted Goodwill In January 2017, the FASB issued ASU No. 2017-04, Intangibles-Goodwill and Other (Topic 350) Simplifying the Test for Goodwill Impairment. This ASU eliminates Step 2 of the goodwill impairment test and simplifies how the amount of an impairment loss is determined. The update is effective for public companies in the beginning of fiscal year 2020 and shall be applied on a prospective basis. The Company will adopt this ASU at the beginning of fiscal year 2020. The Company does not expect the impact of this ASU to be material to its consolidated financial statements. Financial Instruments In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments - Credit Losses (Topic 326) ("ASU 2016-13"). This ASU introduces a new accounting model, the Current Expected Credit Losses model (CECL), which could result in earlier recognition of credit losses and additional disclosures related to credit risk. The CECL model will require the Company to use a forward-looking expected credit loss impairment methodology for the recognition of credit losses for financial instruments at the time the financial asset is originated or acquired. The expected credit losses are adjusted each period for changes in expected lifetime credit losses. This model replaces the multiple existing impairment models in current GAAP, which generally require that a loss be incurred before it is recognized. The new standard will also apply to receivables arising from revenue transactions such as contract assets and accounts receivable and is effective for fiscal years beginning after December 15, 2019. The Company will adopt this ASU at the beginning of fiscal year 2020. The standard will be applied prospectively with an adjustment to retained earnings. The adoption of ASU 2016-13 will not materially impact the consolidated financial statements.

Earnings per Share

Earnings per Share	12 Months Ended
	Dec. 28, 2019
Earnings Per Share [Abstract]
Earnings per Share	Earnings per Share Basic earnings per share is calculated by dividing net income by the weighted average number of common shares outstanding during the period. Diluted earnings per share reflects the potential dilution that could occur if securities or other contracts to issue common stock were exercised or converted into common stock or resulted in the issuance of common stock that then shared in the earnings of the Company. The effect of potentially dilutive securities is not considered during periods of loss or if the effect is anti-dilutive. The weighted average number of shares outstanding in calculating basic earnings per share during fiscal years 2019 , 2018 and 2017 exclude 642,677 , 614,911 and 570,171 non-vested restricted shares, respectively. There were no potentially anti-dilutive securities during fiscal years 2019 , 2018 and 2017 . The following table represents a reconciliation of the net income and weighted average shares outstanding for the calculation of basic and diluted earnings per share during fiscal years 2019 , 2018 and 2017 : Years Ended December 28, 2019 December 29, 2018 December 30, 2017 Numerator: Net income – basic and diluted $ 23,756 $ 26,856 $ 24,006 Denominator: Basic weighted average shares outstanding 12,116,185 10,991,124 10,178,901 Effect of dilutive non-vested restricted shares and units 319,674 401,726 326,319 Effect of issuable shares related to acquisitions 77,175 87,713 157,965 Effect of warrants — 25,903 114,621 Diluted weighted average shares outstanding 12,513,034 11,506,466 10,777,806

Stockholders' Equity (Notes)

Stockholders' Equity (Notes)	12 Months Ended
	Dec. 28, 2019
Equity [Abstract]
Stockholders' Equity	S tockholders' Equity Warrant exercise In conjunction with the Company’s initial public offering on March 26, 2013 , the underwriter received a warrant to acquire up to 140,000 units (“Unit Warrant”). On March 23, 2016, the underwriter paid $1,008 to the Company to exercise the Unit Warrant. Each of the units delivered upon exercise consisted of one share of the Company’s common stock and one warrant to purchase one share of the Company’s common stock at an exercise price of $7.80 per share (“Warrant”), which warrant expired on March 27, 2018. On March 19, 2018, the underwriter paid $1,093 to the Company to exercise the Warrant. On March 21, 2018, the Company delivered 140,000 shares of common stock to the underwriter. Common Stock offering On August 9, 2018, the Company priced an underwritten follow-on offering of 1,270,000 shares of the Company’s common stock (the “2018 Firm Shares”) at an offering price of $79.00 per share. The shares were sold pursuant to an effective registration statement on Form S-3 (Registration No. 333-224392). In addition, a selling stockholder of the Company granted the underwriters of the offering a 30-day option to purchase up to 190,500 shares (the “2018 Option Shares”) of the Company’s common stock at the public offering price less the underwriting discount. On August 13, 2018, the Company closed on the 2018 Firm Shares, for which we received net proceeds of $93,469 after deducting the underwriting discount and estimated offering expenses payable by the Company, and the selling stockholder of the Company closed on the sale of all 2018 Option Shares. The Company did not receive any proceeds associated with the sale of the 2018 Option Shares by the selling stockholder.

Business Acquisitions

Business Acquisitions	12 Months Ended
	Dec. 28, 2019
Business Combinations [Abstract]
Business Acquisitions	Business Acquisitions 2019 Acquisitions On December 20, 2019 (the "Closing Date"), the Company acquired all of the outstanding equity interests in Geospatial Holdings, Inc. and its subsidiaries, including Quantum Spatial, Inc. (collectively "QSI"), a full-service geospatial solutions provider serving the North American market. QSI provides data solutions to public and private sector clients that need geospatial intelligence to mitigate risk, plan for growth, better manage resources, and advance scientific understanding. NV5 Global acquired QSI in an all-cash transaction for $318,000 , which includes excess working capital of $8,781 and closing date cash of approximately $6,677 . The purchase price and other related costs associated with the transaction were financed through the Company's amended and restated credit agreement (the "A&R Credit Agreement") with Bank of America, N.A. and the other lenders party thereto. Pursuant to the A&R Credit Agreement, the lenders provided term commitments of $150,000 in the aggregate in a single draw on the Closing Date and revolving commitments totaling $215,000 . See Note 11, Notes Payable and Other Obligations , for further detail on the A&R Credit Agreement. In order to determine the fair values of tangible and intangible assets required and liabilities assumed for QSI, the Company engaged a third-party independent valuation specialist to assist in the determination of fair values. The final determination of the fair value of certain assets and liabilities will be completed within the one year measurement period as required by ASC Topic 805, Business Combinations ("ASC 805"). The QSI acquisition will necessitate the use of this measurement period to adequately analyze and assess a number of the factors used in establishing the asset and liability fair values as of the acquisition date, including intangible assets, accounts receivable, and certain fixed assets. On November 8, 2019, the Company acquired from GHD Services, Inc. ("GHD") its assets related to the business for forensics and insurance. The GHD forensics and insurance business provides engineering and environmental claim services for insurance companies, law firms, and litigation support. The Company acquired GHD for a cash purchase price of $8,300 . In order to determine the fair values of tangible and intangible assets required and liabilities assumed for GHD, the Company engaged a third-party independent valuation specialist to assist in the determination of fair values. The final determination of the fair value of certain assets and liabilities will be completed within the one year measurement period as required by ASC 805. The GHD acquisition will necessitate the use of this measurement period to adequately analyze and assess a number of the factors used in establishing the asset and liability fair values as of the acquisition date, including accounts receivable. On July 2, 2019, the Company acquired all of the outstanding equity interests in WHPacific, Inc. (“WHPacific”), a provider of design engineering and surveying services serving Washington, Oregon, Idaho, New Mexico, Arizona and California for a cash purchase price of $9,000 . In order to determine the fair values of tangible and intangible assets acquired and liabilities assumed for WHPacific, the Company engaged a third-party independent valuation specialist to assist in the determination of fair values. The final determination of the fair value of certain assets and liabilities will be completed within the one year measurement period as required by ASC 805. The WHPacific acquisition will necessitate the use of this measurement period to adequately analyze and assess a number of the factors used in establishing the asset and liability fair values as of the acquisition date, including accounts receivable. Only July 1, 2019, the Company acquired all of the outstanding equity interests in GeoDesign, Inc. ("GeoDesign"), a geotechnical, environmental, geological, mining and pavement engineering company serving Washington, Oregon, and California. The aggregate purchase price is up to $12,800 , including $8,500 of cash, $2,000 in promissory note (bearing interest at 4.0% ), payable in four equal installments of $500 due on the first, second, third, and fourth anniversaries of July 1, 2019, and $375 of the Company's common stock ( 4,731 shares) issued at the closing date. The purchase price also includes $425 of the Company's common stock payable on the first and second anniversaries of July 1, 2019. Further, the purchase price includes a $1,500 earn-out of cash, which was recorded at the estimated fair value of $198 . In order to determine the fair values of tangible and intangible assets acquired and liabilities assumed for GeoDesign, the Company engaged a third-party independent valuation specialist to assist in the determination of fair values. The GeoDesign acquisition will necessitate the use of this measurement period to adequately analyze and assess a number of the factors used in establishing the asset and liability fair values as of the acquisition date, including accounts receivable. On June 3, 2019, the Company acquired all of the outstanding equity interests in Alta Environmental, L.P. ("Alta"), a consulting firm specializing in air quality, environmental building sciences, water resources, site assessment and remediation as well as environmental health and safety compliance services. The aggregate purchase price is up to $6,500 , including $4,000 of cash and $2,000 in promissory note (bearing interest at 4.0% ), payable in 4 equal installments of $500 due on the first, second, third, and fourth anniversaries of June 3, 2019. Further, the purchase price includes a $500 earn-out of cash, which was recorded at an estimated fair value of $323 . In order to determine the fair values of tangible and intangible assets acquired and liabilities assumed for Alta, the Company engaged a third-party independent valuation specialist to assist in the determination of fair values. The Alta acquisition will necessitate the use of this measurement period to adequately analyze and assess a number of the factors used in establishing the asset and liability fair values as of the acquisition date, including accounts receivable. On June 3, 2019, the Company acquired all of the outstanding equity interests in Page One Consultants ("Page One"), a program management and construction quality assurance firm based in Orlando, Florida. The aggregate purchase price is up to $3,900 , including $2,000 of cash, $1,000 in promissory note (bearing interest at 3.0% ), payable in three equal installments of $333 due on the first, second, and third anniversaries of June 3, 2019, and $200 of the Company's common stock ( 2,647 shares) issued at the closing date. The purchase price also includes a $500 earn-out of cash and stock, which was recorded at an estimated fair value of $448 . In order to determine the fair values of tangible and intangible assets acquired and liabilities assumed for Page One, the Company engaged a third-party independent valuation specialist to assist in the determination of fair values. The Page One acquisition will necessitate the use of this measurement period to adequately analyze and assess a number of the factors used in establishing the asset and liability fair values as of the acquisition date, including accounts receivable. On March 22, 2019, the Company acquired all of the outstanding equity interests in the Sextant Group, Inc. ("The Sextant Group"), a national leading provider of audiovisual, information and communications technology, acoustics consulting, and design services headquartered in Pittsburgh, PA. The Sextant Group provides services throughout the U.S. and is well-known for creating integrated technology solutions for a wide range of public and private sector clients. The aggregate purchase price is up to $11,000 , including $7,000 of cash and $4,000 in promissory note (bearing interest at 4.0% ), payable in 4 equal installments of $1,000 due on the first, second, third, and fourth anniversaries of March 22, 2019. In order to determine the fair values of tangible and intangible assets acquired and liabilities assumed for The Sextant Group, the Company engaged a third-party independent valuation specialist to assist in the determination of fair values. The final determination of the fair value of certain assets and liabilities will be completed within the one year measurement period as required by ASC 805. The Sextant Group acquisition will necessitate the use of this measurement period to adequately analyze and assess a number of the factors used in establishing the asset and liability fair values as of the acquisition date, including accounts receivable. On December 31, 2018, the Company acquired certain assets of Celtic Energy, Inc. ("Celtic"), a nationally recognized energy consulting firm that specialized in energy project management and oversight. The aggregate purchase price is up to $1,900 , including $1,000 in cash, $300 in promissory note (bearing interest at 3.0% ), payable in three equal installments of $100 on the first, second, and third anniversaries of December 31, 2018, and $200 of the Company's common stock ( 3,227 shares) issued at the closing date. The purchase price also includes $200 of the Company's common stock payable on the first anniversary December 31, 2018. Further, the purchase price includes a $200 earn-out of cash, which was recorded at an estimated fair value of $181 . In order to determine the fair values of tangible and intangible assets acquired and liabilities assumed for Celtic, the Company performed a purchase price allocation. 2018 Acquisitions On November 2, 2018 the Company acquired CHI Engineering, Inc. (“CHI”), an infrastructure engineering firm based in Portsmouth, New Hampshire. CHI is a leading provider of engineering, procurement, and construction management services to the liquefied natural gas (“LNG”), petroleum gas (“LPG”) and Natural Gas industries. CHI’s client base includes the majority of LNG facility owner/operators in the U.S. The aggregate purchase price of this acquisition is up to $53,000 , including $30,000 in cash, $15,000 in promissory notes (bearing interest at 3.0% ), payable in four equal installments of $3,750 on the first, second, third and fourth anniversaries of November 2, 2018 and $3,000 of the Company’s common stock ( 36,729 shares) issued at the closing date. In July 2019, the Company received $2,360 from the sellers of CHI, as a working capital adjustment which was recorded as a reduction of the purchase price paid for the acquisition of CHI. The purchase price also includes $3,000 of the Company’s common stock payable in three installments of $1,000 , due on the first, second and third anniversaries of November 2, 2018. The purchase price also includes a $2,000 earn-out of cash (at a 3.0% interest rate which begins to accrue on January 1, 2020), which was recorded at its estimated fair value of $1,547 , based on a probability-weighted approach valuation technique used to determine the fair value of the contingent consideration on the acquisition date. The note and the earn-out are due to related party individuals who became employees of the Company upon the acquisition. In order to determine the fair values of tangible and intangible assets acquired and liabilities assumed for CHI, the Company engaged a third-party independent valuation specialist to assist in the determination of fair values. On August 24, 2018, the Company acquired all of the outstanding equity interests in CALYX Engineers and Consultants, Inc. ("CALYX"), an infrastructure and transportation firm based in Cary, North Carolina. CALYX provides roadway and structure design, transportation planning, water resources, construction services, utility services, building structure design, land development, traffic services, cultural resources, surveying, and environmental services. CALYX serves both public and private clients, including state departments of transportation, municipalities, developers, higher education, and healthcare systems. The acquisition of CALYX will expand our infrastructure engineering service in the southeast United States. The purchase price of this acquisition is $34,000 , subject to customary closing working capital adjustments, including $25,000 in cash, $4,000 in promissory notes (bearing interest at 3.75% ), payable in four installments of $1,000 , due on the first, second, third and fourth anniversaries of August 24, 2018, $3,000 of the Company’s common stock ( 36,379 shares) as of the closing date of the acquisition, and $2,000 in cash payable within 120 days of the closing date. The note is due to related party individuals who became employees of the Company. In order to determine the fair values of tangible and intangible assets acquired and liabilities assumed for CALYX, the Company engaged a third-party independent valuation specialist to assist in the determination of fair values. On February 2, 2018, the Company acquired CSA (M&E) Ltd. (“CSA”), a leading provider of Mechanical, Electrical, and Plumbing (MEP) engineering and sustainability consulting services. CSA provides MEP and sustainability services for the retail, education, healthcare, industrial, corporate, hospitality and infrastructure market sectors with offices in Hong Kong, Macau and the UAE. CSA serves private and public sector clients throughout Asia and the Middle East. The purchase price of this acquisition was up to $4,200 , including $2,000 in cash; $600 in promissory notes (bearing interest at 3.0% ), payable in four installments of $150 , due on the first, second, third and fourth anniversaries of February 2, 2018, the effective date of the acquisition; and $150 of the Company’s common stock ( 2,993 shares) issued as of the closing date. The purchase price also includes $250 of the Company’s common stock payable in two installments of $125 , due on the first and second anniversaries of the acquisition. The purchase price also included a non-interest bearing earn-out of up to $1,200 payable in cash and stock, subject to the achievement of certain agreed upon financial metrics for fiscal year 2018. The earn-out of $1,200 is non-interest bearing and was recorded at its estimated fair value of $899 , based on a probability-weighted approach valuation technique used to determine the fair value of the contingent consideration on the acquisition date. The note and the earn-out are due to a related party individual who became an employee of the Company upon the acquisition. In order to determine the fair values of tangible and intangible assets acquired and liabilities assumed for CSA, the Company engaged a third-party independent valuation specialist to assist in the determination of fair values. On January 12, 2018, the Company acquired all of the outstanding equity interest in Butsko Utility Design, Inc. (“Butsko”). Butsko is leading provider of utility planning and design services serving both public and private sector clients through its offices in Southern California and Washington. The purchase price of this acquisition was up to $4,250 , including $1,500 in cash; $1,000 in promissory notes (bearing interest at 3.0% ), payable in four installments of $250 , due on the first, second, third and fourth anniversaries of January 12, 2018, the effective date of the acquisition; and $300 of the Company’s common stock ( 5,630 shares) issued as of the closing date. The purchase price also includes $600 of the Company’s common stock payable in two installments of $300 , due on the first and second anniversaries of the acquisition. The purchase price also included a non-interest bearing earn-out of up to $850 payable in cash and stock, subject to the achievement of certain agreed upon financial metrics for fiscal year 2018. The earn-out of $850 is non-interest bearing and was recorded at its estimated fair value of $666 , based on a probability-weighted approach valuation technique used to determine the fair value of the contingent consideration on the acquisition date. The note and the earn-out are due to a related party individual who became an employee of the Company upon the acquisition. In order to determine the fair values of tangible and intangible assets acquired and liabilities assumed for Butsko, the Company engaged a third-party independent valuation specialist to assist in the determination of fair values. 2017 Acquisitions On December 22, 2017, we acquired certain assets of Skyscene, LLC (“Skyscene”), a California-based premier aerial survey and mapping company that provides flight services using the latest drone technology. Skyscene operates fixed wing and multirotor UAV’s carrying the most advanced remote sensing equipment. The purchase price of this acquisition was $650 including $250 in cash and $400 in the Company’s common stock ( 7,434 shares) as of the closing date of the acquisition. On September 6, 2017, the Company acquired all of the outstanding equity interests in Marron and Associates, Inc. (“Marron”), a leading environmental services firm with offices in Albuquerque and Las Cruces, New Mexico. Marron provides environmental planning, natural and cultural resources, environmental site assessment, and GIS services. Marron primarily serves public and private clients throughout the Southwest, including the New Mexico Department of Transportation, Bureau of Land Management, Bureau of Indian Affairs, Federal Highway Administration, U.S. Department of Agriculture, U.S. Fish and Wildlife Service, and U.S. Forest Service. The purchase price of this acquisition is up to $990 including $400 in cash, $300 in promissory notes (bearing interest at 3.0% ), payable in three installments of $100 , due on the first, second and third anniversaries of September 6, 2017, the effective date of the acquisition, $67 of the Company’s common stock ( 1,510 shares) as of the closing date of the acquisition and $133 in stock or a combination of cash and shares of the Company’s stock, at its discretion, payable in two equal installments, due on the first and second anniversaries of September 6, 2017.The purchase price also included an earn-out of $90 , subject to the achievement of certain agreed upon metrics for calendar year 2017. The note and the earn-out are due to a related party individual who became an employee of the Company upon the acquisition. The Company internally determined the preliminary fair values of tangible and intangible assets acquired and liabilities assumed. On June 6, 2017, the Company acquired all of the outstanding equity interests in Richard D. Kimball Co. ("RDK"), an established leader in the provision of energy efficiency and mechanical, electric and plumbing (MEP) services based in Boston, Massachusetts. In addition to MEP and fire protection services, RDK offers commissioning services, technology design services, and energy and sustainability services, including Whole Building Energy Modeling and ASHRAE Level Energy Audits, Green Building Certification, Energy Code Consulting, Carbon Emissions Management, and Renewable Energy Management. RDK primarily serves commercial, healthcare, science and technology, education, government, and transportation clients. The purchase price of this acquisition is up to $22,500 , subject to customary closing working capital adjustments, including $15,000 in cash, $5,500 in promissory notes (bearing interest at 3.0% ), payable in four installments of $1,375 , due on the first, second, third and fourth anniversaries of June 6, 2017, $667 of the Company’s common stock ( 18,072 shares) as of the closing date of the acquisition, and $1,333 in stock or a combination of cash and shares of the Company’s stock, at our discretion, payable in two equal installments, due on the first and second anniversaries of June 6, 2017. In order to ultimately determine the fair values of tangible and intangible assets acquired and liabilities assumed for RDK, we engaged a third-party independent valuation specialist to assist in the determination of fair values. On May 4, 2017, the Company acquired all of the outstanding equity interests in Holdrege & Kull, Consulting Engineers and Geologists (“H&K”), a full-service geotechnical engineering firm based in Northern California. H&K provides services to public, municipal and special district, industrial, and private sector clients. The purchase price of this acquisition is up to $2,200 including $1,000 in cash, $600 in promissory notes (bearing interest at 3.0% ), payable in four installments of $150 , due on the first, second, third and fourth anniversaries of May 4, 2017, the effective date of the acquisition, and $100 of the Company’s common stock ( 2,628 shares) as of the closing date of the acquisition. The purchase price also included an interest bearing earn-out of $500 promissory note, subject to the achievement of certain agreed upon metrics for calendar year 2017. The earn-out promissory note is payable in four installments of $125 , due on the first, second, third and fourth anniversaries of May 4, 2017. The earn-out of $500 was recorded at its estimated fair value of $405 , based on a probability-weighted approach valuation technique used to determine the fair value of the contingent consideration on the acquisition date. The note and the earn-out are due to a related party individual who became an employee of the Company upon the acquisition. In order to ultimately determine the fair values of tangible and intangible assets acquired and liabilities assumed for H&K, we engaged a third-party independent valuation specialist to assist in the determination of fair values. On May 1, 2017, the Company acquired all of the outstanding equity interests in Lochrane Engineering Incorporated (“Lochrane”), an Orlando, Florida based civil engineering firm, which specializes in the provision of services on major roadway projects, and its major clients include the Florida Department of Transportation and Florida’s Turnpike Enterprise. The purchase price of this acquisition is up to $4,940 including $2,690 in cash, $2,200 in promissory notes (bearing interest at 3.0% ), payable in four installments of $550 , due on the first, second, third and fourth anniversaries of May 1, 2017, the effective date of the acquisition, $17 of the Company’s common stock ( 441 shares) as of the closing date of the acquisition, and $33 in stock or a combination of cash and shares of the Company’s stock, at our discretion, payable in two equal installments, due on the first and second anniversaries of May 1, 2017. Included in the $2,200 promissory notes, is an earn-out of $550 , subject to the achievement of certain agreed upon metrics for calendar year 2017. The earn-out of $550 is interest bearing and was recorded at its estimated fair value of $413 , based on a probability-weighted approach valuation technique used to determine the fair value of the contingent consideration on the acquisition date. The note and the earn-out are due to a related party individual who became an employee of the Company upon the acquisition. In order to ultimately determine the fair values of tangible and intangible assets acquired and liabilities assumed for Lochrane, we engaged a third-party independent valuation specialist to assist in the determination of fair values. On April 14, 2017, the Company acquired all of the outstanding equity interests in Bock & Clark Corporation (“B&C”), an Akron, Ohio based surveying, commercial zoning, and environmental services firm. The acquisition of B&C will expand our cross-selling opportunities within our infrastructure engineering, surveying, and program management groups and with our financial and transactional real estate clients. The aggregate purchase price consideration paid by the Company in connection with the acquisition was $42,000 , subject to customary closing working capital adjustments, funded entirely in cash. In order to ultimately determine the fair values of tangible and intangible assets acquired and liabilities assumed for Bock & Clark, we engaged a third-party independent valuation specialist to assist in the determination of fair values. The following table summarizes the fair values of the assets acquired and liabilities assumed as of the acquisition dates for acquisitions closed during fiscal years 2019 and 2018 : 2019 2018 QSI Other Total Total Cash $ 6,894 75 6,969 $ 345 Billed and unbilled receivables, net 42,523 21,642 64,165 20,999 Right-of-use assets 6,131 0 6,131 0 Property and equipment 13,626 2,163 15,789 3,122 Prepaid expenses 2,612 997 3,609 589 Other assets 1,317 1,048 2,365 83 Intangible assets: — Customer relationships 64,709 10,423 75,132 32,267 Trade name 58,546 1,365 59,911 2,479 Customer backlog 6,835 1,363 8,198 8,007 Developed technology 32,944 0 32,944 — Other — 814 814 4,306 Total Assets 236,137 39,890 276,027 72,197 Liabilities (23,698 ) (8,324) (32,022 ) (11,589 ) Deferred tax liabilities (39,372 ) (3,779) (43,151 ) (8,903 ) Net assets acquired 173,067 27,787 200,854 51,705 Consideration paid (Cash, Notes and/or stock) 318,004 50,946 368,950 90,516 Contingent earn-out liability (Cash and stock) — 1,004 1,004 3,112 Total Consideration 318,004 51,950 369,954 93,628 Excess consideration over the amounts assigned to the net assets acquired (Goodwill) $ 144,937 24,163 169,100 $ 41,923 Goodwill was recorded based on the amount by which the purchase price exceeded the fair value of the net assets acquired and the amount is attributable to the reputation of the business acquired, the workforce in place and the synergies to be achieved from these acquisitions. See Note 9, Goodwill and Intangible Assets , for further information on goodwill and identified intangibles. The consolidated financial statements of the Company for fiscal years 2019 , 2018 and 2017 include the results of operations from the businesses acquired from their respective dates of acquisition during each of the respective periods as follows: 2019 2018 2017 Gross revenues $ 42,127 $ 33,468 $ 59,048 Income before income taxes $ 3,170 $ 6,677 $ 10,755 General and administrative expense for fiscal years 2019 , 2018 and 2017 included $1,492 , $1,267 and $1,398 , respectively, of acquisition-related costs pertaining to the Company’s acquisition activities. The following table presents the unaudited, pro forma consolidated results of operations (in thousands, except per share amounts) for fiscal years 2019 , 2018 and 2017 as if the acquisitions of QSI, The Sextant Group, Page One, Alta, WHPacific, and GeoDesign had occurred as of January 1, 2018 and as if the acquisition of CHI and CALYX had occurred as of January 1, 2017 . The pro forma information provided below is compiled from the financial statements of CHI, CALYX, The Sextant Group, Page One, Alta, WHPacific, GeoDesign, and QSI and includes pro forma adjustments for amortization expense, adjustments to certain expenses, and the income tax impact of these adjustments. These unaudited pro forma results are presented for informational purposes only and are not necessarily indicative of what the actual results of operations of the Company would have been if the acquisitions and related financing transactions had occurred on the date assumed, nor are they indicative of future results of operations. Years Ended December 28, 2019 December 29, 2018 December 30, 2017 Gross revenues $ 677,109 $ 689,580 $ 430,805 Net income $ 18,421 $ 22,633 $ 22,464 Basic earnings per share $ 1.52 $ 2.05 $ 2.19 Diluted earnings per share $ 1.47 $ 1.95 $ 2.07 Pro forma results for 2019 were adjusted to exclude acquisition-related costs incurred by NV5 Global and QSI. Adjustments were also made to adjust amortization of intangible assets to reflect fair value of identified assets acquired, to record the effects of extinguishing the debt of QSI and replacing it with the debt of NV5 Global, and to record the income tax effect of these adjustments. Adjustments were made to the 2018 pro forma results to adjust amortization of intangible assets to reflect fair value of identified assets acquired, to record the effect of extinguishing the debt of QSI and replacing it with the debt of NV5 Global, and to record the income tax effect of these adjustments. All other acquisitions were not material to the Company’s consolidated financial statements both individually and in the aggregate.

Billed and Unbilled Receivables

Billed and Unbilled Receivables	12 Months Ended
	Dec. 28, 2019
Receivables [Abstract]
Billed and Unbilled Receivables	Billed and Unbilled Receivables Billed and Unbilled Receivables consists of the following: December 28, 2019 December 29, 2018 Billed receivables $ 134,900 $ 101,482 Less: allowance for doubtful accounts (3,860 ) (3,158 ) Billed receivables, net $ 131,041 $ 98,324 Unbilled receivables $ 80,639 $ 44,799 Less: allowance for doubtful accounts (1,211 ) (1,388 ) Unbilled receivables, net $ 79,428 $ 43,411 Activity in the allowance for doubtful accounts consisted of the following: December 28, 2019 December 29, 2018 Balance as of the beginning of the year $ 4,546 $ 3,642 Provision for doubtful accounts 1,239 797 Write-offs of uncollectible accounts (714 ) (301 ) Other (1) — 408 Balance as of the end of the year $ 5,071 $ 4,546 (1) Includes allowances from new business acquisitions.

Property and Equipment, Net

Property and Equipment, Net	12 Months Ended
	Dec. 28, 2019
Property, Plant and Equipment [Abstract]
Property, plant and Equipment, Net	Property and Equipment, net Property and equipment, net consists of the following: December 28, 2019 December 29, 2018 Office furniture and equipment $ 4,198 $ 2,328 Computer equipment 10,704 11,640 Survey and field equipment 24,165 5,526 Leasehold improvements 6,266 2,541 Total 45,333 22,035 Less: accumulated depreciation (19,600 ) (10,358 ) Property and equipment, net $ 25,733 $ 11,677 Depreciation expense for fiscal years 2019 , 2018 and 2017 was $5,327 , $4,331 and $2,818 , respectively.

Goodwill and Intangible Assets

Goodwill and Intangible Assets	12 Months Ended
	Dec. 28, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	Goodwill and Intangible Assets Goodwill The changes in the carrying value by reportable segment for the fiscal years 2019 and 2018 were as follows: Fiscal Year 2019 December 29, 2018 Acquisitions Disposed/Adjustments December 28, 2019 INF $ 69,255 $ 162,814 $ (814 ) $ 231,255 BTS 71,675 6,286 — 77,961 Total $ 140,930 $ 169,100 $ (814 ) $ 309,216 Fiscal Year 2018 December 30, 2017 Acquisitions Disposed/Adjustments December 29, 2018 INF $ 28,675 $ 40,472 $ 108 $ 69,255 BTS 70,224 1,451 — 71,675 Total $ 98,899 $ 41,923 $ 108 $ 140,930 Goodwill of $9,574 and $14,350 from acquisitions in 2019 and 2018 , respectively, is expected to be deductible for income tax purposes. During 2019 , the Company received $2,360 from the sellers of CHI as a working capital adjustment which was recorded as a reduction of goodwill and the purchase price paid for the acquisition of CHI. In addition, during 2019 there were fair value adjustments that increased goodwill by $1,546 . During 2018 , the Company revised its allocation of purchase price for 2017 acquisitions and increased goodwill by $108 . Intangible assets Intangible assets, net, at December 28, 2019 and December 29, 2018 consist of the following: December 28, 2019 December 29, 2018 Gross Carrying Amount Accumulated Amortization Net Amount Gross Carrying Amount Accumulated Amortization Net Amount Finite-lived intangible assets: Customer relationships (1) $ 176,088 $ (29,198 ) $ 146,890 $ 100,956 $ (18,724 ) $ 82,232 Trade name (2) 10,253 (8,593 ) 1,660 8,888 (6,469 ) 2,419 Customer backlog (1) 24,198 (12,435 ) 11,763 16,000 (6,730 ) 9,270 Favorable lease (3) — — — 552 (197 ) 355 Non-compete (4) 9,369 (5,105 ) 4,264 8,554 (3,074 ) 5,480 Developed technology (5) 32,944 (106 ) 32,838 — — — Total finite-lived intangible assets 252,851 (55,436 ) 197,415 134,950 (35,194 ) 99,756 Indefinite-lived intangible assets: QSI trade name 58,546 — 58,546 $ — $ — $ — Total indefinite-lived intangible assets 58,546 — 58,546 $ — $ — $ — Total intangible assets $ 311,397 $ (55,436 ) $ 255,961 $ 134,950 $ (35,194 ) $ 99,756 (1) Amortized on a straight-line basis over estimated lives ( 1 to 12 years ) (2) Amortized on a straight-line basis over their estimated lives ( 1 to 3 years ) (3) Amortized on a straight-line basis over the remaining lease term of 9 years (4) Amortized on a straight-line basis over their contractual lives ( 4 to 5 years ) (5) Amortized on a straight-line basis over their estimated lives ( 5 to 7 years ) The following table summarizes the weighted average useful lives of definite-lived intangible assets acquired during 2019 and 2018 : 2019 2018 Customer relationships 10.0 10.0 Trade name 2.0 1.8 Customer backlog 3.0 1.8 Developed technology 7.0 — Non-compete 4.0 4.1 Amortization expense for fiscal years 2019 , 2018 and 2017 was $20,488 , $13,052 and $10,310 respectively. As of December 28, 2019 , the future estimated aggregate amortization related to finite-lived intangible assets for the next five fiscal years and thereafter is as follows: Amount 2020 $ 31,398 2021 26,901 2022 22,569 2023 21,450 2024 21,155 Thereafter 73,941 Total $ 197,415

Accrued Liabilities

Accrued Liabilities	12 Months Ended
	Dec. 28, 2019
Payables and Accruals [Abstract]
Accrued Liabilities	Accrued Liabilities Accrued liabilities consist of the following: December 28, 2019 December 29, 2018 Current portion of lease liability $ 13,108 $ — Accrued vacation 10,048 7,994 Payroll and related taxes 12,146 8,136 Benefits 4,637 1,598 Unrecognized tax benefits 887 548 Professional liability reserve 1,083 157 Deferred rent — 779 Other 5,523 1,641 Total $ 47,432 $ 20,853

Notes Payable and Other Obligat

Notes Payable and Other Obligations	12 Months Ended
	Dec. 28, 2019
Payables and Accruals [Abstract]
Notes Payable and Other Obligations	Notes Payable and Other Obligations Notes payable and other obligations consists of the following: December 28, 2019 December 29, 2018 Senior credit facility 320,457 $ — Uncollateralized promissory notes 36,217 40,001 Finance leases 2,707 2,092 Other obligations 2,884 4,893 Debt issuance costs, net of amortization (4,078) — Total Notes Payable and Other Obligations 358,187 46,986 Current portion of notes payable and other obligations (25,332 ) (17,139 ) Notes payable and other obligations, less current portion 332,854 $ 29,847 Senior Credit Facility On December 20, 2019 (the "Closing Date"), the Company amended and restated its Credit Agreement (the "A&R Credit Agreement"), dated December 7, 2016, as amended on December 20, 2018, with Bank of America, N.A. ("Bank of America"), as administrative agent, swingline lender and letter of credit issuer, the other lenders party thereto, and certain of the Company's subsidiaries as guarantors. Pursuant to the A&R Credit Agreement, the lenders provided term commitments of $150.0 million in the aggregate in a single draw on the Closing Date to fund the acquisition of QSI and various costs and expenses relating thereto and revolving commitments totaling $215.0 million in the aggregate. The revolving commitment is available through December 20, 2024 (the "Maturity Date"), at which time the term commitments and revolving commitments will be due and payable in full. An aggregate amount of $320.5 million was drawn under the A&R Credit Agreement on the closing date to fund the QSI acquisition and repay previously existing borrowings. The Senior Credit Facility is secured by a first priority lien on substantially all of the assets of the Company. The A&R Credit Agreement also includes an accordion feature permitting the Company to request an increase in either the term facility or the revolver facility under the A&R Credit Agreement by an additional amount of up to $100.0 million in the aggregate. Borrowings under the term facility amortize at the rate of 5.0% per annum for the first two years of the facility and thereafter at the rate of 7.5% per annum until the Maturity Date. Borrowings under the A&R Credit Agreement bear interest at variable rates described below, which are, at our option, tied to a Eurocurrency rate equal to LIBOR (London Interbank Offered Rate) plus an applicable margin or a base rate denominated in U.S. dollars. Interest rates are subject to change based on our consolidated leverage ratio. The consolidated leverage ratio is the ratio of our pro forma consolidated funded indebtedness to our pro forma consolidated EBITDA for the most recently completed measurement period. The A&R Credit Agreement contains covenants that may have the effect of limiting the ability of the Company and its subsidiaries to, among other things, merge with or acquire other entities, enter into a transaction resulting in a Change in Control, create certain new liens, incur certain additional indebtedness, engage in certain transactions with affiliates, or engage in new lines of business or sell a substantial part of their assets. The A&R Credit Agreement also contains financial covenants that requires us to maintain a consolidated fixed charge coverage ratio of no less than 1.20 to 1.00 as of the end of any measurement period. In addition, we are required to maintain a consolidated leverage ratio as described below: Measurement Period Ending Maximum Consolidated Leverage Ratio Closing Date through June 30, 2020 4.25 to 1.00 July 1, 2020 through September 30, 2020 4.00 to 1.00 October 1, 2020 through December 31, 2020 3.75 to 1.00 January 1, 2021 and thereafter 3.50 to 1.00 As of December 28, 2019 , we were in compliance with the financial covenants. The A&R Credit Agreement also contains customary events of default, including (but not limited to) a default in the payment of principal or, following an applicable grace period, interest, breaches of the our covenants or warranties under the A&R Credit Agreement, payment default or acceleration of certain indebtedness of the Company or any subsidiary, certain events of bankruptcy, insolvency or liquidation involving the Company or any subsidiaries, certain judgments or uninsured losses, changes in control and certain liabilities related to ERISA based plans. The A&R Credit Agreement limits the payment of cash dividends (together with certain other payments that would constitute a "Restricted Payment" within the meaning of the A&R Credit Agreement and generally including dividends, stock repurchases and certain other payments in respect to warrants, options, and other rights to acquire equity securities) to no more than $10,000 in any fiscal year, so long as no default shall exist at the time of or arise as a result from such payment. Total debt issuance costs incurred and capitalized in connection with the issuance of the A&R Credit Agreement were $3,676 . Total amortization of debt issuance costs was $131 during 2019. Other Obligations On July 1, 2019, the Company acquired GeoDesign. The purchase price allowed for the payment of $425 in shares of the Company's stock or a combination of cash and shares of the Company's stock, at our discretion, payable on the first and second anniversary of July 1, 2019. At December 28, 2019 , the outstanding balance of this obligation was $382 . On June 3, 2019, the Company acquired Page One. The purchase price allowed for the payment of $200 in shares of the Company's stock or a combination of cash and shares of the Company's stock, at our discretion, payable on the first anniversary of June 3, 2019. At December 28, 2019 , the outstanding balance of this obligation was $181 . On December 31, 2018, the Company acquired certain assets of Celtic. The purchase price allowed for the payment of $200 in shares of the company's stock or a combination of cash and shares of the Company's stock, at our discretion, payable on the first anniversary of December 31, 2018. At December 28, 2019 , the outstanding balance of this obligation was $181 . On November 2, 2018, the Company acquired CHI. The purchase price allowed for the payment of $3,000 in shares of the Company’s stock or a combination of cash and shares of the Company’s stock, at our discretion, payable in three equal annual installments. At December 28, 2019 and December 29, 2018 , the outstanding balance of this obligation was $1,754 . On February 2, 2018, the Company acquired CSA. The purchase price allowed for the payment of $250 in shares of the Company’s stock or a combination of cash and shares of the Company’s stock, at our discretion, payable in two equal annual installments. At December 28, 2019 and December 29, 2018 , the outstanding balance of this obligation was $111 and $222 , respectively. On January 12, 2018, the Company acquired all of the outstanding equity interest in Butsko. The purchase price allowed for the payment of $600 in shares of the Company’s stock or a combination of cash and shares of the Company’s stock, at our discretion, payable in two equal annual installments. At December 28, 2019 and December 29, 2018 , the outstanding balance of this obligation was $267 and $534 , respectively. On September 6, 2017, the Company acquired all of the outstanding equity interest in Marron. The purchase price allowed for the payment of $133 in shares of the Company’s stock or a combination of cash and shares of the Company’s stock, at our discretion, payable in two equal annual installments. There was no outstanding balance on this obligation as of December 28, 2019 . At December 29, 2018 , the outstanding balance of this obligation was $55 . On June 6, 2017, the Company acquired all of the outstanding equity interest in RDK. The purchase price allowed for the payment of $1,333 in shares of the Company’s stock or a combination of cash and shares of the Company’s stock, at our discretion, payable in two equal annual installments. There was no outstanding balance on this obligation as of December 28, 2019 . At December 29, 2018 , the outstanding balance of this obligation was $504 . On May 20, 2016, the Company acquired all of the outstanding equity interests of Dade Moeller. The purchase price allowed for the payment of $3,000 in shares of the Company’s stock or a combination of cash and shares of the Company’s stock, at our discretion, payable in three equal annual installments of $1,000 . There was no outstanding balance on this obligation as of December 28, 2019 . At December 29, 2018 , the outstanding balance of this obligation was $936 . Uncollateralized Promissory Notes On July 1, 2019, the Company acquired GeoDesign. The purchase price included an uncollateralized $2,000 promissory note bearing interest at 4.0% ("GeoDesign Note") and payable in four equal annual installments. The outstanding balance of the GeoDesign Note was $2,000 as of December 28, 2019 . On June 3, 2019, the Company acquired Alta. The purchase price included an uncollateralized $2,000 promissory note bearing interest at 4.0% ("Alta Note") and payable in four equal annual installments. The outstanding balance of the Alta Note was $2,000 as of December 28, 2019 . On June 3, 2019, the Company acquired Page One. The purchase price included an uncollateralized $1,000 promissory note bearing interest at 3.0% ("Page One Note") and payable in three equal annual installments. The outstanding balance of the Page One Note was $1,000 as of December 28, 2019 . On March 22, 2019, the Company acquired The Sextant Group. The purchase price included an uncollateralized $4,000 promissory note bearing interest at 4.0% ("The Sextant Group Note") and payable in four equal annual installments. The outstanding balance of The Sextant Group Note was $3,140 as of December 28, 2019 . On December 31, 2018, the Company acquired certain assets of Celtic. The purchase price included an uncollateralized $300 promissory note bearing interest at 3.0% (the "Celtic Note") payable in three equal annual installments. The outstanding balance of the Celtic Note was $300 as of December 28, 2019 . On November 2, 2018, the Company acquired CHI. The purchase price included an uncollateralized $15,000 promissory note bearing interest at 3.0% (the "CHI Note") payable in four equal annual installments. The outstanding balance of the CHI Note was $11,250 and $15,000 as of December 28, 2019 and December 29, 2018 , respectively. On August 24, 2018, the Company acquired CALYX. The purchase price included an uncollateralized $4,000 promissory note bearing interest at 3.75% payable in four equal annual installments of $1,000 . The outstanding balance of the CALYX Note was $3,000 and $4,000 as of December 28, 2019 and December 29, 2018 , respectively. On February 2, 2018, the Company acquired CSA. The purchase price included an uncollateralized $600 promissory note bearing interest at 3.0% (the "CSA Note") payable in four equal annual installments of $150 . The outstanding balance of the CSA Note was $450 and $600 as of December 28, 2019 and December 29, 2018 , respectively. On January 12, 2018, the Company acquired all of the outstanding equity interest in Butsko. The purchase price included an uncollateralized $1,000 promissory note bearing interest at 3.0% (the "Butsko Note") payable in four equal annual installments of $250 . The outstanding balance of the Butsko Note was $750 and $1,000 as of December 28, 2019 and December 29, 2018 , respectively. On September 6, 2017, the Company acquired all of the outstanding interests in Marron. The purchase price included an uncollateralized $300 promissory note bearing interest at 3.0% (the "Marron Note") payable in three equal annual installments of $100 , The outstanding balance of the Marron Note was $100 and $200 as of December 28, 2019 and December 29, 2018 , respectively. On June 6, 2017, the Company acquired all of the outstanding equity interest in RDK. The purchase price included an uncollateralized $5,500 promissory note bearing interest at 3.0% (the "RDK Note") payable in four equal annual installments of $1,375 . The outstanding balance of the RDK Note was $2,750 and $4,125 as of December 28, 2019 and December 29, 2018 , respectively. On May 4, 2017, the Company acquired all of the outstanding equity interest in H&K. The purchase price included an uncollateralized $600 promissory note bearing interest at 3.0% (the "H&K Note") payable in four equal annual installments of $150 . The outstanding balance of the H&K Note was $300 and $450 as of December 28, 2019 and December 29, 2018 , respectively. On May 1, 2017, the Company acquired all of the outstanding equity interest in Lochrane. The purchase price included an uncollateralized $1,650 promissory note bearing interest at 3.0% (the "Lochrane Note") payable in four equal annual installments of $413 . The outstanding balance of the Lochrane Note was $825 and $1,238 as of December 28, 2019 and December 29, 2018 , respectively. On December 6, 2016, the Company acquired all of the outstanding interests of CivilSource. The purchase price included an uncollateralized $3,500 promissory note bearing interest at 3.0% (the "CivilSource Note") payable in four equal annual installments of $875 . The outstanding balance of the CivilSource Note was $1,502 and $2,625 as of December 28, 2019 and December 29, 2018 , respectively. On November 30, 2016, the Company acquired all of the outstanding interests of Hanna. The purchase price included an uncollateralized $2,700 promissory note bearing interest at 3.0% (the "Hanna Note") payable in four equal annual installments of $675 . The outstanding balance of the Hanna Note was $675 and $1,350 as of December 28, 2019 and December 29, 2018 , respectively. On October 26, 2016, the Company acquired all of the outstanding interests of JBA. The purchase price included an uncollateralized $7,000 promissory note bearing interest at 3.0% (the "JBA Note") payable in five equal annual installments of $1,400 . The outstanding balance of the JBA Note was $4,163 and $4,200 as of December 28, 2019 and December 29, 2018 , respectively. On September 12, 2016, the Company acquired certain assets of Weir. The purchase price included an uncollateralized $500 promissory note bearing interest at 3.0% (the "Weir Note") payable in four equal annual installments of $125 . The outstanding balance of the Weir Note was $125 and $250 as of December 28, 2019 and December 29, 2018 , respectively. On May 20, 2016, the Company acquired all of the outstanding equity interests of Dade Moeller. The purchase price included an aggregate of $6,000 of uncollateralized promissory notes bearing interest at 3.0% (the "Dade Moeller Notes") payable in four equal annual installments of $1,500 . The outstanding balance of the Dade Moeller Notes was $1,497 and $3,036 as of December 28, 2019 and December 29, 2018 , respectively. On July 1, 2015, the Company acquired all of the outstanding equity interests of RBA. The purchase price included an uncollateralized $4,000 promissory notes bearing interest at 3.0% (the "RBA Note") payable in four equal annual installments. There was no outstanding balance on the RBA Note as of December 28, 2019 . The outstanding balance of the RBA Note was $1,000 as of December 29, 2018 . On January 30, 2015, the Company acquired all of the outstanding equity interests of JLA. The purchase price included an uncollateralized $1,250 promissory note bearing interest at 3.5% (the "JLA Note") payable in four equal annual installments of $313 . There was no outstanding balance on the JLA Note as of December 28, 2019 . As of December 29, 2018 , the outstanding balance of the JLA Note was $313 . Future contractual maturities of long-term debt as of December 28, 2019 are as follows: Fiscal Year Amount 2020 $ 26,039 2021 20,144 2022 19,400 2023 13,578 2024 283,104 Total $ 362,265 As of December 28, 2019 and December 29, 2018 , the carrying amount of debt obligations approximates their fair values based on Level 2 inputs.

Contingent Consideration

Contingent Consideration	12 Months Ended
	Dec. 28, 2019
Commitments and Contingencies Disclosure [Abstract]
Contingent Consideration	Contingent Consideration The following table summarizes the changes in the carrying value of estimated contingent consideration: December 28, 2019 December 29, 2018 Contingent consideration, beginning of the year $ 4,698 $ 1,890 Additions for acquisitions 1,316 3,112 Reduction of liability for payments made (1,938 ) (728 ) Decrease (increase) of liability related to re-measurement of fair value (74 ) 424 Total contingent consideration, end of the period 4,002 4,698 Current portion of contingent consideration 1,954 1,845 Contingent consideration, less current portion $ 2,048 $ 2,853

Leases

Leases	12 Months Ended
	Dec. 28, 2019
Leases [Abstract]
Leases	Leases The Company primarily leases property under operating leases and has five equipment operating leases for aircrafts. Our property operating leases consist of various office facilities, which we lease from unrelated parties. We use a portfolio approach to account for such leases due to the similarities in characteristics and apply an incremental borrowing rate based on estimates of rates the Company would pay for senior collateralized loans over a similar term. Our office leases with an initial term of 12 months or less are not recorded on the balance sheet. We account for lease components (e.g. fixed payments including rent, real estate taxes and common area maintenance costs) as a single lease component. Some of our leases include one or more options to renew the lease term at our sole discretion; however, these are not included in the calculation of our lease liability or ROU lease asset because they are not reasonably certain of exercise. We also lease vehicles through a fleet leasing program. The payments for the vehicles are based on the terms selected. We have determined that it is reasonably certain that the leased vehicles will be held beyond the period in which the entire capitalized value of the vehicle has been paid to the lessor. As such, the capitalized value is the delivered price of the vehicle. Our vehicle leases are classified as financing leases. Supplemental balance sheet information related to the Company's operating and finance leases is as follows: Leases Classification December 28, 2019 Assets Operating lease assets Right-of-use lease asset, net (1) $ 46,313 Finance lease assets Property and equipment, net (1) 2,371 Total leased assets $ 48,685 Liabilities Current Operating Accrued liabilities $ (13,108 ) Finance Current portion of notes payable and other obligations (1,022 ) Noncurrent Operating Long-term lease liability (34,573 ) Finance Notes payable and other obligations, less current portion (1,685 ) Total lease liabilities $ (50,388 ) (1) At December 28, 2019 , operating right of-use lease assets and finance lease assets are recorded net of accumulated amortization of $9,657 and $1,592 , respectively. Supplemental balance sheet information related to the Company's operating and finance leases is as follows: Weighted - Average Remaining Lease Term (Years) December 28, 2019 Operating leases 5.0 Finance leases 2.8 Weighted - Average Discount Rate Operating leases 4% Finance leases 7% Supplemental cash flow information related to the Company's operating and finance lease liabilities is as follows: Fiscal Year Ended December 28, 2019 Operating cash flows from operating leases $ 10,988 Financing cash flows from finance leases $ 796 Right-of-use assets obtained in exchange for lease obligations Operating leases $ 20,731 The following table summarizes the components of lease cost recognized in the consolidated statements of net income and comprehensive income: Fiscal Year Ended Lease Cost Classification December 28, 2019 Operating lease cost Facilities and facilities related $ 11,538 Finance lease cost Amortization of right of use assets Depreciation and amortization 1,245 Interest on lease liabilities Interest expense 98 Total lease cost 12,881 As of December 28, 2019 , maturities of the Company's lease liabilities under its long-term operating leases and finance leases for the next five fiscal years and thereafter are as follows: Fiscal Year Operating Leases Finance Leases 2020 $ 14,620 $ 990 2021 12,492 875 2022 8,693 708 2023 6,205 438 2024 3,890 199 Thereafter 6,776 11 Total lease payments 52,676 3,221 Less: Interest (4,995 ) (514 ) Present value of lease liabilities $ 47,681 $ 2,707 As of December 29, 2018 , future minimum payments by fiscal year for the Company's non-cancelable operating leases was as follows: Fiscal Year Amount 2019 $ 9,506 2020 8,054 2021 7,224 2022 5,364 2023 4,504 Thereafter 7,704 Total minimum lease payments $ 42,356
Leases	Leases The Company primarily leases property under operating leases and has five equipment operating leases for aircrafts. Our property operating leases consist of various office facilities, which we lease from unrelated parties. We use a portfolio approach to account for such leases due to the similarities in characteristics and apply an incremental borrowing rate based on estimates of rates the Company would pay for senior collateralized loans over a similar term. Our office leases with an initial term of 12 months or less are not recorded on the balance sheet. We account for lease components (e.g. fixed payments including rent, real estate taxes and common area maintenance costs) as a single lease component. Some of our leases include one or more options to renew the lease term at our sole discretion; however, these are not included in the calculation of our lease liability or ROU lease asset because they are not reasonably certain of exercise. We also lease vehicles through a fleet leasing program. The payments for the vehicles are based on the terms selected. We have determined that it is reasonably certain that the leased vehicles will be held beyond the period in which the entire capitalized value of the vehicle has been paid to the lessor. As such, the capitalized value is the delivered price of the vehicle. Our vehicle leases are classified as financing leases. Supplemental balance sheet information related to the Company's operating and finance leases is as follows: Leases Classification December 28, 2019 Assets Operating lease assets Right-of-use lease asset, net (1) $ 46,313 Finance lease assets Property and equipment, net (1) 2,371 Total leased assets $ 48,685 Liabilities Current Operating Accrued liabilities $ (13,108 ) Finance Current portion of notes payable and other obligations (1,022 ) Noncurrent Operating Long-term lease liability (34,573 ) Finance Notes payable and other obligations, less current portion (1,685 ) Total lease liabilities $ (50,388 ) (1) At December 28, 2019 , operating right of-use lease assets and finance lease assets are recorded net of accumulated amortization of $9,657 and $1,592 , respectively. Supplemental balance sheet information related to the Company's operating and finance leases is as follows: Weighted - Average Remaining Lease Term (Years) December 28, 2019 Operating leases 5.0 Finance leases 2.8 Weighted - Average Discount Rate Operating leases 4% Finance leases 7% Supplemental cash flow information related to the Company's operating and finance lease liabilities is as follows: Fiscal Year Ended December 28, 2019 Operating cash flows from operating leases $ 10,988 Financing cash flows from finance leases $ 796 Right-of-use assets obtained in exchange for lease obligations Operating leases $ 20,731 The following table summarizes the components of lease cost recognized in the consolidated statements of net income and comprehensive income: Fiscal Year Ended Lease Cost Classification December 28, 2019 Operating lease cost Facilities and facilities related $ 11,538 Finance lease cost Amortization of right of use assets Depreciation and amortization 1,245 Interest on lease liabilities Interest expense 98 Total lease cost 12,881 As of December 28, 2019 , maturities of the Company's lease liabilities under its long-term operating leases and finance leases for the next five fiscal years and thereafter are as follows: Fiscal Year Operating Leases Finance Leases 2020 $ 14,620 $ 990 2021 12,492 875 2022 8,693 708 2023 6,205 438 2024 3,890 199 Thereafter 6,776 11 Total lease payments 52,676 3,221 Less: Interest (4,995 ) (514 ) Present value of lease liabilities $ 47,681 $ 2,707 As of December 29, 2018 , future minimum payments by fiscal year for the Company's non-cancelable operating leases was as follows: Fiscal Year Amount 2019 $ 9,506 2020 8,054 2021 7,224 2022 5,364 2023 4,504 Thereafter 7,704 Total minimum lease payments $ 42,356

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 28, 2019
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Litigation, Claims and Assessments The Company is subject to certain claims and lawsuits typically filed against the engineering, consulting and construction profession, alleging primarily professional errors or omissions. The Company carries professional liability insurance, subject to certain deductibles and policy limits, against such claims. However, in some actions, parties are seeking damages that exceed our insurance coverage or for which we are not insured. While management does not believe that the resolution of these claims will have a material adverse effect, individually or in aggregate, on its financial position, results of operations or cash flows, management acknowledges the uncertainty surrounding the ultimate resolution of these matters.

Stock-Based Compensation

Stock-Based Compensation	12 Months Ended
	Dec. 28, 2019
Share-based Payment Arrangement [Abstract]
Stock-Based Compensation	Stock-Based Compensation In October 2011, the Company’s stockholders approved the 2011 Equity Incentive Plan, which was subsequently amended and restated in March 2013 (as amended, the “2011 Equity Plan”). The 2011 Equity Plan provides directors, executive officers, and other employees of the Company with additional incentives by allowing them to acquire ownership interest in the business and, as a result, encouraging them to contribute to the Company’s success. The Company may provide these incentives through the grant of stock options, stock appreciation rights, restricted stock, restricted stock units, performance shares and units, and other cash-based or stock-based awards. As of December 28, 2019 , 1,237,029 shares of common stock are authorized and reserved for issuance under the 2011 Equity Plan. This reserve automatically increases on each January 1 from 2014 through 2023, by an amount equal to the smaller of (i) 3.5% of the number of shares issued and outstanding on the immediately preceding December 31, or (ii) an amount determined by the Company’s Board of Directors. The restricted shares of common stock granted generally provide for service-based vesting after two to four years following the grant date. The following summarizes the activity of restricted stock awards during fiscal years 2019 , 2018 and 2017 : Share Units Weighted Average Grant Date Fair Value Unvested shares as of December 31, 2016 502,773 $ 19.35 Granted 199,419 $ 38.72 Vested (93,805 ) $ 9.61 Forfeited (25,336 ) $ 28.79 Unvested shares as of December 30, 2017 583,051 $ 27.13 Granted 187,087 $ 65.15 Vested (127,870 ) $ 19.98 Forfeited (15,357 ) $ 32.14 Unvested shares as of December 29, 2018 626,911 $ 39.81 Granted 275,220 $ 70.90 Vested (207,039 ) $ 20.41 Forfeited (42,415 ) $ 53.24 Unvested shares as of December 28, 2019 652,677 $ 58.20 Share-based compensation expense relating to restricted stock awards during fiscal years ended 2019 , 2018 and 2017 was $10,430 , $6,697 and $4,011 , respectively. Approximately $21,264 of deferred compensation, which is expected to be recognized over the remaining weighted average vesting period of 2 years, is unrecognized as of December 28, 2019 . The total fair value of restricted shares vested during fiscal years 2019 , 2018 and 2017 was $14,680 , $7,422 and $3,626 , respectively.

Employee Benefit Plan

Employee Benefit Plan	12 Months Ended
	Dec. 28, 2019
Retirement Benefits [Abstract]
Employee Benefit Plan	Employee Benefit Plan The Company sponsors a 401(k) Profit Sharing and Savings Plan (the “401(k) Plan”) for which employees meeting certain age and length of service requirements may contribute up to the defined statutory limit. The 401(k) Plan allows for the Company to make matching and profit sharing contributions in such amounts as may be determined by the Board of Directors. The Company assesses its matching contributions on a quarterly basis based primarily on Company performance in previous periods. The Company contributed $1,323 , $676 and $1,940 , respectively, to the 401(k) Plan for fiscal years 2019 , 2018 and 2017 , respectively.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 28, 2019
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Income tax expense for years 2019 , 2018 and 2017 consisted of the following: Years Ended December 28, 2019 December 29, 2018 December 30, 2017 Current: Federal $ 8,059 $ 7,261 $ 9,341 State 3,800 2,911 2,265 Foreign (49 ) 276 263 Total current income tax expense 11,810 10,448 11,869 Deferred: Federal (5,160 ) (2,924 ) (10,439 ) State (1,474 ) (661 ) (803 ) Total deferred income tax (benefit) (6,634 ) (3,585 ) (11,242 ) . Total income tax expense $ 5,176 $ 6,863 $ 627 Temporary differences comprising the net deferred income tax liability shown in the Company’s consolidated balance sheets were as follows: December 28, 2019 December 29, 2018 Deferred tax asset: Lease liabilities $ 17,651 $ — Tax carryforwards 7,767 — Accrued compensation 6,682 4,348 Allowance for doubtful accounts 1,789 1,044 Deferred rent — 201 Other 327 78 Total deferred tax asset $ 34,216 $ 5,671 Deferred tax liability: Acquired intangibles $ (60,045 ) $ (17,248 ) Right-of-use assets (17,189 ) — Depreciation and amortization (6,289 ) (2,444 ) Cash to accrual adjustment (2,569 ) (1,962 ) Other (1,465 ) (241 ) Total deferred tax liability (87,557 ) (21,895 ) Net deferred tax liability $ (53,341 ) $ (16,224 ) As of December 28, 2019 and December 29, 2018 , the Company had net non-current deferred tax liabilities of $53,341 and $16,224 , respectively. No valuation allowance against the Company’s deferred income tax assets is needed as of December 28, 2019 and December 29, 2018 as it is more-likely-than-not that the positions will be realized upon settlement. Deferred income tax liabilities primarily relate to intangible assets and accounting basis adjustments where the Company has a future obligation for tax purposes. During 2019 and 2018, the Company recorded a deferred tax liability of $43,151 and $8,903 , respectively, in conjunction with the purchase price allocation of the intangible assets associated with acquisitions. Total income tax expense was different than the amount computed by applying the Federal statutory rate as follows: Years Ended December 28, 2019 December 29, 2018 December 30, 2017 Tax at federal statutory rate $ 6,076 $ 7,081 $ 8,622 Stock based compensation (2,808 ) (1,014 ) (1,016 ) State taxes, net of Federal benefit 1,990 1,424 714 Federal and state tax credits (1,247 ) (923 ) (250 ) Changes in unrecognized tax position 425 111 506 Domestic production activities deduction — — (936 ) Transition tax — 110 357 Effect of change in income tax rate — 31 (6,249 ) Other 740 43 (1,121 ) Total income tax expense $ 5,176 $ 6,863 $ 627 On December 22, 2017 the Tax Cuts and Jobs Act (“2017 Tax Reform”) was enacted in the United States. Among its many provisions, the 2017 Tax Reform reduced the U.S. corporate income tax rate from 35% to 21% , effective January 1, 2018. The 2017 Tax Reform required a one-time transition tax on undistributed foreign earnings and created a new provision designed to tax global intangible low-taxed income (“GILTI”). Also, the SEC issued guidance in Staff Accounting Bulletin No. 118 which provided for a measurement period of up to one year after the enactment for companies to complete their accounting for the 2017 Tax Reform. As a result of the 2017 Tax Reform, during the fourth quarter of 2017 , the Company recorded a decrease of $6,249 to its deferred tax assets and liabilities, with a corresponding adjustment to deferred income tax expense. In addition, during the fourth quarter of 2017 , the Company recorded a provisional liability of $ 357 with a corresponding adjustment to income tax expense related to the one-time transition tax on undistributed foreign earnings. The provisional adjustment related to the 2017 Tax Reform was determined using reasonable estimates. During the fiscal year ended December 29, 2018 , the Company recognized a $110 adjustment to the provisional amount recorded as of December 30, 2017 . The Company’s consolidated effective income tax rate was 17.8% , 20.4% and 2.5% for fiscal years 2019 , 2018 and 2017 , respectively. The difference between the effective income tax rate and the combined statutory federal and state income tax rate was primarily due to excess tax benefits from share-based payments and federal credits, offset by other permanent items. Also contributing to the lower effective tax rate for fiscal year 2017 was the re-measurement of the Company's deferred tax assets and liabilities as a result of the change in the U.S. corporate income tax rate and the Federal domestic production activities deduction. The Company and its subsidiaries file income tax returns in the U.S. federal jurisdiction and various state and foreign jurisdictions. The Company evaluates tax positions for recognition using a more-likely-than-not recognition threshold, and those tax positions eligible for recognition are measured as the largest amount of tax benefit that is greater than 50% likely of being realized upon the effective settlement with a taxing authority that has full knowledge of all relevant information. The California Franchise Tax Board (“CFTB”) challenged research and development tax credits generated for the years 2012 to 2014. During the fourth quarter of 2017 , the Company settled with the CFTB and paid $839 for research and development tax credits for the years 2005 through 2011. Fiscal years 2012 through 2019 are considered open tax years in the State of California and 2016 through 2019 in the U.S. federal jurisdiction and other state and foreign jurisdictions. The Company’s 2014 U.S. federal income tax return was reviewed by the Internal Revenue Service and closed with no change during the second quarter of 2018 . As of December 28, 2019 and December 29, 2018, the Company had $887 and $548 , respectively, of gross unrecognized tax benefits, which if recognized, $769 and $548 would affect our effective tax rate. It is not expected that there will be a significant change in the unrecognized tax benefits in the next 12 months. A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows: December 28, 2019 December 29, 2018 December 30, 2017 Balance, beginning of period $ 548 $ 437 $ 770 Additions based on tax positions related to the current year 124 45 49 Additions for tax positions of prior years 338 66 525 Lapse of statute of limitations (123 ) — Reductions for positions of prior years — — (68 ) Settlement — — (839 ) Balance, end of period $ 887 $ 548 $ 437 The Company records accrued interest and penalties related to unrecognized tax benefits in income tax expense. Accrued interest and penalties related to unrecognized tax benefits in the Consolidated Balance Sheet were $204

Reportable Segments

Reportable Segments	12 Months Ended
	Dec. 28, 2019
Segment Reporting [Abstract]
Reportable Segments	Reportable Segments The Company’s Chief Executive Officer is the chief operating decision maker and organized the Company into two operating and reportable segments as follows: • Infrastructure (INF) includes our engineering, civil program management, construction quality assurance, testing, and inspection, and geospatial solutions. • Building, Technology & Sciences (BTS) , which includes our energy, environmental and building program management practices. The Company evaluates the performance of these reportable segments based on their respective operating income before the effect of amortization expense related to acquisitions and other unallocated corporate expenses. The Company accounts for inter-segment revenues and transfers as if the sales and transfers were to third parties. All intercompany balances and transactions are eliminated in consolidation. On December 20, 2019, the Company acquired Geospatial Holdings, Inc. and its subsidiaries, including Quantum Spatial, Inc. (collectively "QSI"), a full-service geospatial solutions provider. QSI's financial results for the period subsequent to the acquisition are consolidated and reported under the Company's INF reportable segment. In the future, the Company may re-evaluate the structure of its internal organization as a result of the QSI acquisition. The following tables set forth summarized financial information concerning our reportable segments: Years Ended December 28, 2019 December 29, 2018 December 30, 2017 Gross revenues INF $ 334,458 $ 257,353 $ 185,238 BTS 178,419 164,739 152,304 Elimination of inter- segment revenues (3,939 ) (4,011 ) (4,508 ) Total gross revenues $ 508,938 $ 418,081 $ 333,034 Segment income before taxes INF $ 54,583 $ 43,832 $ 32,245 BTS 28,138 26,656 21,018 Total Segment income before taxes 82,721 70,488 53,263 Corporate (1) (53,789 ) (36,769 ) (28,630 ) Total income before taxes $ 28,932 $ 33,719 $ 24,633 (1) Includes amortization of intangibles of $20,488 , $13,052 and $10,310 for the fiscal years ended 2019 , 2018 and 2017 , respectively. December 28, 2019 December 29, 2018 Assets INF $ 776,835 $ 228,979 BTS 23,976 155,112 Corporate (1) 92,326 55,330 Total assets $ 893,137 $ 439,421 (1) Corporate assets consist of intercompany eliminations and assets not allocated to segments including cash and cash equivalents and certain other assets. Substantially all of the Company's assets are located in the United States. Upon adoption of Topic 606, the Company disaggregates its gross revenues from contracts with customers by geographic location, customer-type and contract-type for each of its reportable segments. Disaggregated revenues include the elimination of inter-segment revenues which has been allocated to each segment. The Company believes this best depicts how the nature, amount, timing and uncertainty of its revenues and cash flows are affected by economic factors. No sales to an individual customer or country other than the United States accounted for more than 10% of gross revenue for fiscal years 2019, 2018, or 2017. Gross revenue, classified by the major geographic areas in which our customers were located, were as follows: Fiscal Year Ended December 28, 2019 December 29, 2018 INF BTS Total INF BTS Total United States $ 331,161 $ 171,246 $ 502,407 $ 254,723 $ 150,696 $ 405,419 Foreign — 6,531 6,531 — 12,662 12,662 Total gross revenues $ 331,161 $ 177,777 $ 508,938 $ 254,723 $ 163,358 $ 418,081 Gross revenue by customer were as follows: Fiscal Year Ended December 28, 2019 December 29, 2018 INF BTS Total INF BTS Total Public and quasi-public sector $ 271,935 $ 66,544 $ 338,479 $ 233,395 $ 45,393 $ 278,788 Private sector 59,226 111,233 170,459 21,328 117,965 139,293 Total gross revenues $ 331,161 $ 177,777 $ 508,938 $ 254,723 $ 163,358 $ 418,081 Gross revenues by contract type were as follows: Fiscal Year Ended December 28, 2019 December 29, 2018 INF BTS Total INF BTS Total Cost-reimbursable contracts $ 318,112 $ 139,406 $ 457,518 $ 254,365 $ 128,738 $ 383,103 Fixed-unit price contracts 13,049 38,371 51,420 358 34,620 34,978 Total gross revenues $ 331,161 $ 177,777 $ 508,938 $ 254,723 $ 163,358 $ 418,081

Quarterly Financial Information

Quarterly Financial Information (Unaudited)	12 Months Ended
	Dec. 28, 2019
Quarterly Financial Information Disclosure [Abstract]
Quarterly Financial Information (Unaudited)	Quarterly Financial Information (Unaudited) Management believes the following unaudited quarterly financial information for fiscal years 2019 and 2018 , which is derived from the Company’s unaudited interim financial statements, reflects all adjustments necessary for a fair statement of the results of operations. The fluctuations between periods is a result of acquisitions made during 2019 and 2018 (See Note 5, Business Acquisitions , for further information on the Company's acquisitions). Quarter Ended First Quarter Second Quarter Third Quarter Fourth Quarter Fiscal Year Ended December 28, 2019 Gross revenues $ 117,335 $ 127,974 $ 131,032 $ 132,598 Gross profit $ 55,430 $ 61,440 $ 63,496 $ 65,017 Income from operations $ 7,411 $ 9,597 $ 7,825 $ 6,374 Income before income tax expense $ 7,060 $ 9,140 $ 7,403 $ 5,329 Net income and comprehensive income $ 5,543 $ 8,794 $ 5,843 $ 3,575 Basic earnings per share $ 0.46 $ 0.73 $ 0.48 $ 0.29 Diluted earnings per share $ 0.44 $ 0.70 $ 0.46 $ 0.28 Quarter Ended First Quarter Second Quarter Third Quarter Fourth Quarter Fiscal Year Ended December 29, 2018 Gross revenues $ 94,534 $ 104,018 $ 104,185 $ 115,344 Gross profit $ 46,631 $ 50,702 $ 49,974 $ 54,097 Income from operations $ 6,301 $ 9,350 $ 9,974 $ 10,060 Income before income tax expense $ 5,690 $ 8,700 $ 9,523 $ 9,806 Net income and comprehensive income $ 4,292 $ 7,620 $ 7,285 $ 7,659 Basic earnings per share $ 0.42 $ 0.73 $ 0.65 $ 0.64 Diluted earnings per share $ 0.39 $ 0.69 $ 0.62 $ 0.62

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 28, 2019
Accounting Policies [Abstract]
Basis of Presentation and Principles of Consolidation	Basis of Presentation and Principles of Consolidation
Fiscal Year	Fiscal Year Effective March 7, 2017, the Audit Committee of our Board of Directors and the Board of Directors approved a change in our fiscal year-end and financial accounting cycle. Beginning January 1, 2017, the Company commenced reporting its financial results on a 52/53 week fiscal year ending on the Saturday closest to December 31st (whether or not in the following calendar year), with interim calendar quarters ending on the Saturday closest to the end of such calendar quarter (whether or not in the following calendar quarter).
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts in the consolidated financial statements and accompanying notes. These estimates and assumptions are based on management’s most recent assessment of underlying facts and circumstances using the most recent information available. Actual results could differ significantly from these estimates and assumptions, and the differences could be material. Estimates and assumptions are evaluated periodically and adjusted when necessary. The more significant estimates affecting amounts reported in the consolidated financial statements include the following: • Fair value estimates used in accounting for business combinations including the valuation of identifiable intangible assets and contingent consideration • Fair value estimates in determining the fair value of our reporting units for goodwill impairment assessment • Revenue recognition over time • Allowances for uncollectible accounts
Cash and Cash Equivalents	Cash and Cash Equivalents Cash and cash equivalents include cash on deposit with financial institutions and investments in high quality overnight money market funds, all of which have maturities of three months or less when purchased. The Company from time to time may be exposed to credit risk with its bank deposits in excess of the Federal Deposit Insurance Corporation insurance limits and with uninsured money market investments. Management believes cash and cash equivalent balances are not exposed to significant credit risk due to the financial position of the depository institutions in which those deposits are held.
Concentration of Credit Risk	Concentration of Credit Risk Trade receivable balances carried by the Company are comprised of accounts from a diverse client base across a broad range of industries and are not collateralized. However, 27% , 30% and 32% of the Company’s gross revenues for fiscal years 2019, 2018 and 2017, respectively, are from California-based projects. The Company did not have any clients representing more than 10% of our gross revenues during 2019, 2018 or 2017. During fiscal years 2019, 2018 and 2017 approximately 68% , 67% and 68% , respectively, of our gross revenues was attributable to the public and quasi-public sector. Management continually evaluates the creditworthiness of these and future clients and provides for bad debt reserves as necessary.
Fair Value of Financial Instruments	Fair Value of Financial Instruments Fair value is defined as the amount that would be received for selling an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date and is measured using inputs in one of the following three categories: Level 1 measurements are based on unadjusted quoted prices in active markets for identical assets or liabilities that we have the ability to access. Valuation of these items does not entail a significant amount of judgment. Level 2 measurements are based on quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active or market data other than quoted prices that are observable for the assets or liabilities. Level 3 measurements are based on unobservable data that are supported by little or no market activity and are significant to the fair value of the assets or liabilities. The Company considers cash and cash equivalents, accounts receivable, accounts payable, income taxes payable, accrued liabilities and debt obligations to meet the definition of financial instruments. As of December 28, 2019 and December 29, 2018 , the carrying amount of cash and cash equivalents, accounts receivable, accounts payable, income taxes payable and accrued liabilities approximate their fair value due to the relatively short period of time between their origination and their expected realization or payment. The carrying amounts of debt obligations approximate their fair values as the terms are comparable to terms currently offered by local lending institutions for arrangements with similar terms to industry peers with comparable credit characteristics. The Company applies the provisions of the Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) 805, Business Combinations , in the accounting for its acquisitions, which requires recognition of the assets acquired and the liabilities assumed at their acquisition date fair values, separately from goodwill. Goodwill as of the acquisition date is measured as the excess of consideration transferred and the net of the acquisition date fair values of the tangible and identifiable intangible assets acquired and liabilities assumed. The allocation of the purchase price to identifiable intangible assets is based on valuations performed to determine the fair values of such assets as of the acquisition dates. Generally, the Company engages a third-party independent valuation specialist to assist in management’s determination of fair values of tangible and intangible assets acquired and liabilities assumed. The fair values of earn-out arrangements are included as part of the purchase price of the acquired companies on their respective acquisition dates. The Company estimates the fair value of contingent earn-out payments as part of the initial purchase price and records the estimated fair value of contingent consideration as a liability on the consolidated balance sheet. Changes in the estimated fair value of contingent earn-out payments are included in General and Administrative expenses on the Consolidated Statements of Net Income and Comprehensive Income. Several factors are considered when determining contingent consideration liabilities as part of the purchase price, including whether (i) the valuation of the acquisitions is not supported solely by the initial consideration paid, and the contingent earn-out formula is a critical and material component of the valuation approach to determining the purchase price; and (ii) the former owners of the acquired companies that remain as key employees receive compensation other than contingent earn-out payments at a reasonable level compared with the compensation of other key employees. The contingent earn-out payments are not affected by employment termination.
Property and Equipment	Property and Equipment Property and equipment is stated at cost. Property and equipment acquired in a business combination is stated at fair value at the acquisition date. The Company capitalizes the cost of improvements to property and equipment that increase the value or extend the useful lives of the assets. Normal repair and maintenance costs are expensed as incurred. Depreciation and amortization is computed on a straight-line basis over the following estimated useful lives of the assets. Leasehold improvements are amortized on a straight-line basis over the lesser of their estimated useful lives or the remaining terms of the related lease agreement. Asset Depreciation Period (in years) Office furniture and equipment 4 Computer equipment 3 Survey and field equipment 5 Leasehold improvements Lesser of the estimated useful lives or remaining term of the lease Property and equipment balances are periodically reviewed by management for impairment whenever events or changes in circumstances indicate that the carrying value of the asset may not be recoverable. If an indicator of impairment exists, the Company compares the estimated future cash flows of the asset, on an undiscounted basis, to the carrying value of the asset. If the undiscounted cash flows exceed the carrying value, no impairment is indicated. If the undiscounted cash flows do not exceed the carrying value, then impairment is measured as the difference between fair value and carrying value, with fair value typically based on a discounted cash flow model. During fiscal years 2019 , 2018 and 2017 , no impairment charge relating to property and equipment was recognized.
Goodwill and Intangible Assets	Goodwill and Intangible Assets Goodwill is the excess of consideration paid for an acquired entity over the amounts assigned to assets acquired, including other identifiable intangible assets and liabilities assumed in a business combination. To determine the amount of goodwill resulting from a business combination, we perform an assessment to determine the acquisition date fair value of the acquired company’s tangible and identifiable intangible assets and liabilities. The Company evaluates goodwill annually for impairment on August 1 or whenever events or changes in circumstances indicate the asset may be impaired. An entity has the option to first assess qualitative factors to determine whether the existence of events or circumstances leads to a determination that it is more likely than not that the fair value of a reporting unit is less than its carrying amount. These qualitative factors include: macroeconomic and industry conditions, cost factors, overall financial performance and other relevant entity-specific events. If the entity determines that this threshold is met, then performing the two-step quantitative impairment test is unnecessary. The two-step impairment test requires a comparison of the carrying value of the assets and liabilities associated with a reporting unit, including goodwill, with the fair value of the reporting unit. The Company determines fair value through multiple valuation techniques, and weights the results accordingly. NV5 Global is required to make certain subjective and complex judgments in assessing whether an event of impairment of goodwill has occurred, including assumptions and estimates used to determine the fair value of its reporting units. If the carrying value of its reporting unit exceeds the fair value of its reporting unit, the Company would calculate the implied fair value as compared to the carrying value to determine the appropriate impairment charge, if any. Identifiable intangible assets primarily include customer backlog, customer relationships, finite and indefinite-lived trade names, non-compete agreements, and developed technology. Amortizable intangible assets are amortized on a straight-line basis over their estimated useful lives and reviewed for impairment whenever events or changes in circumstances indicate that the assets may be impaired. If an indicator of impairment exists, the Company compares the estimated future cash flows of the asset, on an undiscounted basis, to the carrying value of the asset. If the undiscounted cash flows exceed the carrying value, no impairment is indicated. If the undiscounted cash flows do not exceed the carrying value, then impairment, if any, is measured as the difference between fair value and carrying value, with fair value typically based on a discounted cash flow model. During fiscal years 2019 , 2018 and 2017 , no impairment charge relating to goodwill and intangible assets was recognized. See Note 9, Goodwill and Intangible Assets , for further information on goodwill and identified intangibles.
Earnings Per Share
Revenue Recognition	Revenue Recognition On the first day of fiscal year 2018, we adopted ASC Topic 606, Revenue from Contracts with Customers (“Topic 606”), using the modified retrospective approach to all contracts that were not completed as of the beginning of fiscal year 2018. We utilize the contract method, which allows companies to account for contracts on a contract by contract basis. For our time and materials contracts, we apply the as-invoiced practical expedient, which permits us to recognize revenue as the right to invoice for services performed. The new standard did not materially affect our consolidated net income, financial position, or cash flows. To determine the proper revenue recognition method, we evaluate whether two or more contracts should be combined and accounted for as one single contract and whether the combined or single contract should be accounted for as more than one performance obligation. The majority of our contracts have a single performance obligation as the promise to transfer the individual goods or services is not separately identifiable from other promises in the contracts and, therefore, is not distinct. The Company’s performance obligations are satisfied as work progresses or at a point in time. Revenue on our cost-reimbursable contracts is recognized over time using direct costs incurred or direct costs incurred to date as compared to the estimated total direct costs for performance obligations because it depicts the transfer of control to the customer. Contract costs include labor, subcontractors’ costs and other direct costs. Gross revenues from services transferred to customers over time accounted for 90% of the Company’s revenues for the period ended December 28, 2019 . Gross revenue from services transferred to customers at a point in time is recognized when the customer obtains control of the asset, which is generally upon delivery and acceptance by the customer of the reports and/or analysis performed. Gross revenue from services transferred to customers at a point in time accounted for 10% and 8% of the Company’s revenues for the period ended December 28, 2019 and December 29, 2018, respectively. As of December 28, 2019 , the Company had $607,482 of remaining performance obligations, of which 493,468 is expected to be recognized over the next 12 months and the majority of the balance over the next 24 months. Contracts for which work authorizations have been received are included in performance obligations. Most of our government contracts are multi-year contracts for which funding is appropriated on an annual basis, therefore performance obligations include only those amounts that have been funded and authorized and does not reflect the full amounts we may receive over the term of such contracts. In the case of non-government contracts and project awards, performance obligations include future revenue at contract or customary rates, excluding contract renewals or extensions that are at the discretion of the client. For contracts with a not-to-exceed maximum amount, we include revenue from such contracts in performance obligations to the extent of the remaining estimated amount. Contract modifications are common in the performance of our contracts. Contracts modified typically result from changes in scope, specifications, design, performance, sites, or period of completion. In most cases, contract modifications are for services that are not distinct, and, therefore, are accounted for as part of the existing contract. Contract estimates are based on various assumptions to project the outcome of future events. These assumptions are dependent upon the accuracy of a variety of estimates, including engineering progress, achievement of milestones, labor productivity and cost estimates. Due to uncertainties inherent in the estimation process, it is possible that actual completion costs may vary from estimates. If estimated total costs on contracts indicate a loss or reduction to the percentage of total contract revenues recognized to date, these losses or reductions are recognized in the period in which the revisions are known. The effect of revisions to revenues, estimated costs to complete contracts, including penalties, incentive awards, change orders, claims, anticipated losses and others are recorded on the cumulative catch-up basis in the period in which the revisions are identified and the loss can be reasonably estimated. Such revisions could occur in any reporting period and the effects on the results of operations for that reporting period may be material depending on the size of the project or the adjustment. During the period ended December 28, 2019 , the cumulative catch-up adjustment for contract modifications was not material. A significant amount of the Company’s revenues are derived under multi-year contracts. The Company enters into contracts with its clients that contain two principal types of pricing provisions: cost-reimbursable and fixed-unit price. The majority of the Company’s contracts are cost-reimbursable contracts that fall under the low-risk subcategory of time and materials contracts. Cost-reimbursable contracts consist of the following: • Time and materials contracts, which are common for smaller scale professional and technical consulting and certification services projects. Under these types of contracts, there is no predetermined fee. Instead, the Company negotiates hourly billing rates and charges the clients based upon actual hours expended on a project. In addition, any direct project expenditures are passed through to the client and are typically reimbursed. These contracts may have an initial not-to-exceed or guaranteed maximum price provision. • Cost-plus contracts are the predominant contracting method used by U.S. federal, state, and local governments. Under these types of contracts, the Company charges clients for its costs, including both direct and indirect costs, plus a negotiated fee. The total estimated cost plus the negotiated fee represents the total contract value. • Lump-sum contracts typically require the performance of all of the work under the contract for a specified lump-sum fee, subject to price adjustments if the scope of the project changes or unforeseen conditions arise. Many of the Company’s lump-sum contracts are negotiated and arise in the design of projects with a specified scope and project deliverables. In most cases, we can bill additional fees if the construction schedule is modified and lengthened. Fixed-unit price contracts typically require the performance of an estimated number of units of work at an agreed price per unit, with the total payment under the contract determined by the actual number of units performed. Federal Acquisition Regulations (“FAR”), which are applicable to the Company’s federal government contracts and may be incorporated in local and state agency contracts, limit the recovery of certain specified indirect costs on contracts. Cost-plus contracts covered by FAR or certain state and local agencies also may require an audit of actual costs and provide for upward or downward adjustments if actual recoverable costs differ from billed recoverable costs. Contract Balances The timing of revenue recognition, billings and cash collections results in billed receivables, unbilled receivables (contract assets), and billings in excess of costs and estimated earnings on uncompleted contracts (contract liabilities) on the Consolidated Balance Sheet. Billed receivables, net represents amounts billed to clients that remain uncollected as of the balance sheet date. The amounts are stated at their estimated realizable value. The Company maintains an allowance for doubtful accounts to provide for the estimated amount of receivables that will not be collected. The allowance is estimated based on management’s evaluation of the contracts involved and the financial condition of clients. Factors the Company considers include, but are not limited to: • Client type (governmental or commercial client) • Historical performance • Historical collection trends • General economic conditions Billed receivables are generally collected within less than 12 months. The allowance is increased by the Company’s provision for doubtful accounts which is charged against income. All recoveries on receivables previously charged off are included in income, while direct charge-offs of receivables are deducted from the allowance. Unbilled receivables, net represents recognized amounts pending billing pursuant to contract terms or accounts billed after period end, and are expected to be billed and collected within the next 12 months. Generally, billing occurs subsequent to revenue recognition, resulting in contract assets. Unbilled receivables (contract assets) are generally classified as current. In certain circumstances, the contract may allow for billing terms that result in the cumulative amounts billed in excess of revenues recognized. The liability “Billings in excess of costs and estimated earnings on uncompleted contracts” represents billings in excess of revenues recognized on these contracts as of the reporting date. This liability is generally classified as current. During fiscal 2019 , the Company performed services and recognized $7,625 of revenue related to its contract liabilities that existed as of December 29, 2018 .
Advertising	Advertising Advertising costs are charged to expense in the period incurred and amounted to $939 , $1,019 and $1,048 during fiscal years 2019 , 2018 and 2017 , respectively, which is included in General and Administrative Expenses on the accompanying Consolidated Statements of Net Income and Comprehensive Income.
Income Taxes	Income Taxes The Company accounts for income taxes in accordance with ASC Topic No. 740 “ Income Taxes ” (“Topic No. 740”). Deferred income taxes reflect the impact of temporary differences between amounts of assets and liabilities for financial reporting purposes and such amounts as measured by tax laws. A valuation allowance against the Company’s deferred tax assets is recorded when it is more likely than not that some portion or all of the deferred tax assets will not be realized. In determining the need for a valuation allowance, management is required to make assumptions and to apply judgment, including forecasting future earnings, taxable income, and the mix of earnings in the jurisdictions in which the Company operates. Management periodically assesses the need for a valuation allowance based on the Company’s current and anticipated results of operations. The need for and the amount of a valuation allowance can change in the near term if operating results and projections change significantly. The Company recognizes the consolidated financial statement benefit of a tax position only after determining that the relevant tax authority would more likely than not sustain the position following an audit. For tax positions meeting the more likely-than-not threshold, the amount recognized in the consolidated financial statements is the largest benefit that has a greater than 50 percent likelihood of being realized upon ultimate settlement with the relevant tax authority. The Company applies the uncertain tax position guidance to all tax positions for which the statute of limitations remains open. The Company’s policy is to classify interest and penalties as income tax expense.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 28, 2019
Accounting Policies [Abstract]
Schedule of property plant and equipment, estimated useful life	Leasehold improvements are amortized on a straight-line basis over the lesser of their estimated useful lives or the remaining terms of the related lease agreement. Asset Depreciation Period (in years) Office furniture and equipment 4 Computer equipment 3 Survey and field equipment 5 Leasehold improvements Lesser of the estimated useful lives or remaining term of the lease

Earnings per Share (Tables)

Earnings per Share (Tables)	12 Months Ended
	Dec. 28, 2019
Earnings Per Share [Abstract]
Schedule of reconciliation of the net income and weighted average shares outstanding for the calculation of basic and diluted earnings per share	The following table represents a reconciliation of the net income and weighted average shares outstanding for the calculation of basic and diluted earnings per share during fiscal years 2019 , 2018 and 2017 : Years Ended December 28, 2019 December 29, 2018 December 30, 2017 Numerator: Net income – basic and diluted $ 23,756 $ 26,856 $ 24,006 Denominator: Basic weighted average shares outstanding 12,116,185 10,991,124 10,178,901 Effect of dilutive non-vested restricted shares and units 319,674 401,726 326,319 Effect of issuable shares related to acquisitions 77,175 87,713 157,965 Effect of warrants — 25,903 114,621 Diluted weighted average shares outstanding 12,513,034 11,506,466 10,777,806

Business Acquisitions (Tables)

Business Acquisitions (Tables)	12 Months Ended
	Dec. 28, 2019
Business Combinations [Abstract]
Summary of the fair values of the assets acquires and liabilities assumed	The following table summarizes the fair values of the assets acquired and liabilities assumed as of the acquisition dates for acquisitions closed during fiscal years 2019 and 2018 : 2019 2018 QSI Other Total Total Cash $ 6,894 75 6,969 $ 345 Billed and unbilled receivables, net 42,523 21,642 64,165 20,999 Right-of-use assets 6,131 0 6,131 0 Property and equipment 13,626 2,163 15,789 3,122 Prepaid expenses 2,612 997 3,609 589 Other assets 1,317 1,048 2,365 83 Intangible assets: — Customer relationships 64,709 10,423 75,132 32,267 Trade name 58,546 1,365 59,911 2,479 Customer backlog 6,835 1,363 8,198 8,007 Developed technology 32,944 0 32,944 — Other — 814 814 4,306 Total Assets 236,137 39,890 276,027 72,197 Liabilities (23,698 ) (8,324) (32,022 ) (11,589 ) Deferred tax liabilities (39,372 ) (3,779) (43,151 ) (8,903 ) Net assets acquired 173,067 27,787 200,854 51,705 Consideration paid (Cash, Notes and/or stock) 318,004 50,946 368,950 90,516 Contingent earn-out liability (Cash and stock) — 1,004 1,004 3,112 Total Consideration 318,004 51,950 369,954 93,628 Excess consideration over the amounts assigned to the net assets acquired (Goodwill) $ 144,937 24,163 169,100 $ 41,923
Results of operations from any business acquired	The consolidated financial statements of the Company for fiscal years 2019 , 2018 and 2017 include the results of operations from the businesses acquired from their respective dates of acquisition during each of the respective periods as follows: 2019 2018 2017 Gross revenues $ 42,127 $ 33,468 $ 59,048 Income before income taxes $ 3,170 $ 6,677 $ 10,755
Pro forma consolidated results of operations	Years Ended December 28, 2019 December 29, 2018 December 30, 2017 Gross revenues $ 677,109 $ 689,580 $ 430,805 Net income $ 18,421 $ 22,633 $ 22,464 Basic earnings per share $ 1.52 $ 2.05 $ 2.19 Diluted earnings per share $ 1.47 $ 1.95 $ 2.07

Billed and Unbilled Receivabl_2

Billed and Unbilled Receivables (Tables)	12 Months Ended
	Dec. 28, 2019
Receivables [Abstract]
Schedule of accounts, notes, loans and financing receivable	Billed and Unbilled Receivables consists of the following: December 28, 2019 December 29, 2018 Billed receivables $ 134,900 $ 101,482 Less: allowance for doubtful accounts (3,860 ) (3,158 ) Billed receivables, net $ 131,041 $ 98,324 Unbilled receivables $ 80,639 $ 44,799 Less: allowance for doubtful accounts (1,211 ) (1,388 ) Unbilled receivables, net $ 79,428 $ 43,411
Allowance for Credit Losses on Financing Receivables	Activity in the allowance for doubtful accounts consisted of the following: December 28, 2019 December 29, 2018 Balance as of the beginning of the year $ 4,546 $ 3,642 Provision for doubtful accounts 1,239 797 Write-offs of uncollectible accounts (714 ) (301 ) Other (1) — 408 Balance as of the end of the year $ 5,071 $ 4,546 (1) Includes allowances from new business acquisitions.

Property and Equipment, Net (Ta

Property and Equipment, Net (Tables)	12 Months Ended
	Dec. 28, 2019
Property, Plant and Equipment [Abstract]
Property, plant and equipment	Property and equipment, net consists of the following: December 28, 2019 December 29, 2018 Office furniture and equipment $ 4,198 $ 2,328 Computer equipment 10,704 11,640 Survey and field equipment 24,165 5,526 Leasehold improvements 6,266 2,541 Total 45,333 22,035 Less: accumulated depreciation (19,600 ) (10,358 ) Property and equipment, net $ 25,733 $ 11,677

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	12 Months Ended
	Dec. 28, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of goodwill	The changes in the carrying value by reportable segment for the fiscal years 2019 and 2018 were as follows: Fiscal Year 2019 December 29, 2018 Acquisitions Disposed/Adjustments December 28, 2019 INF $ 69,255 $ 162,814 $ (814 ) $ 231,255 BTS 71,675 6,286 — 77,961 Total $ 140,930 $ 169,100 $ (814 ) $ 309,216 Fiscal Year 2018 December 30, 2017 Acquisitions Disposed/Adjustments December 29, 2018 INF $ 28,675 $ 40,472 $ 108 $ 69,255 BTS 70,224 1,451 — 71,675 Total $ 98,899 $ 41,923 $ 108 $ 140,930
Schedule of finite-lived intangible assets	Intangible assets, net, at December 28, 2019 and December 29, 2018 consist of the following: December 28, 2019 December 29, 2018 Gross Carrying Amount Accumulated Amortization Net Amount Gross Carrying Amount Accumulated Amortization Net Amount Finite-lived intangible assets: Customer relationships (1) $ 176,088 $ (29,198 ) $ 146,890 $ 100,956 $ (18,724 ) $ 82,232 Trade name (2) 10,253 (8,593 ) 1,660 8,888 (6,469 ) 2,419 Customer backlog (1) 24,198 (12,435 ) 11,763 16,000 (6,730 ) 9,270 Favorable lease (3) — — — 552 (197 ) 355 Non-compete (4) 9,369 (5,105 ) 4,264 8,554 (3,074 ) 5,480 Developed technology (5) 32,944 (106 ) 32,838 — — — Total finite-lived intangible assets 252,851 (55,436 ) 197,415 134,950 (35,194 ) 99,756 Indefinite-lived intangible assets: QSI trade name 58,546 — 58,546 $ — $ — $ — Total indefinite-lived intangible assets 58,546 — 58,546 $ — $ — $ — Total intangible assets $ 311,397 $ (55,436 ) $ 255,961 $ 134,950 $ (35,194 ) $ 99,756 (1) Amortized on a straight-line basis over estimated lives ( 1 to 12 years ) (2) Amortized on a straight-line basis over their estimated lives ( 1 to 3 years ) (3) Amortized on a straight-line basis over the remaining lease term of 9 years (4) Amortized on a straight-line basis over their contractual lives ( 4 to 5 years ) (5) Amortized on a straight-line basis over their estimated lives ( 5 to 7 years )
Schedule of Acquired Finite-Lived Intangible Assets by Major Class	The following table summarizes the weighted average useful lives of definite-lived intangible assets acquired during 2019 and 2018 : 2019 2018 Customer relationships 10.0 10.0 Trade name 2.0 1.8 Customer backlog 3.0 1.8 Developed technology 7.0 — Non-compete 4.0 4.1
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense	As of December 28, 2019 , the future estimated aggregate amortization related to finite-lived intangible assets for the next five fiscal years and thereafter is as follows: Amount 2020 $ 31,398 2021 26,901 2022 22,569 2023 21,450 2024 21,155 Thereafter 73,941 Total $ 197,415

Accrued Liabilities (Tables)

Accrued Liabilities (Tables)	12 Months Ended
	Dec. 28, 2019
Payables and Accruals [Abstract]
Schedule of accrued liabilities	December 28, 2019 December 29, 2018 Current portion of lease liability $ 13,108 $ — Accrued vacation 10,048 7,994 Payroll and related taxes 12,146 8,136 Benefits 4,637 1,598 Unrecognized tax benefits 887 548 Professional liability reserve 1,083 157 Deferred rent — 779 Other 5,523 1,641 Total $ 47,432 $ 20,853

Notes Payable and Other Oblig_2

Notes Payable and Other Obligations (Tables)	12 Months Ended
	Dec. 28, 2019
Payables and Accruals [Abstract]
Schedule of long-term debt instruments	Notes payable and other obligations consists of the following: December 28, 2019 December 29, 2018 Senior credit facility 320,457 $ — Uncollateralized promissory notes 36,217 40,001 Finance leases 2,707 2,092 Other obligations 2,884 4,893 Debt issuance costs, net of amortization (4,078) — Total Notes Payable and Other Obligations 358,187 46,986 Current portion of notes payable and other obligations (25,332 ) (17,139 ) Notes payable and other obligations, less current portion 332,854 $ 29,847
Schedule of line of credit	In addition, we are required to maintain a consolidated leverage ratio as described below: Measurement Period Ending Maximum Consolidated Leverage Ratio Closing Date through June 30, 2020 4.25 to 1.00 July 1, 2020 through September 30, 2020 4.00 to 1.00 October 1, 2020 through December 31, 2020 3.75 to 1.00 January 1, 2021 and thereafter 3.50 to 1.00
Schedule of maturities of long-term debt	Future contractual maturities of long-term debt as of December 28, 2019 are as follows: Fiscal Year Amount 2020 $ 26,039 2021 20,144 2022 19,400 2023 13,578 2024 283,104 Total $ 362,265

Contingent Consideration (Table

Contingent Consideration (Tables)	12 Months Ended
	Dec. 28, 2019
Commitments and Contingencies Disclosure [Abstract]
Schedule of business acquisitions by acquisition, contingent consideration	The following table summarizes the changes in the carrying value of estimated contingent consideration: December 28, 2019 December 29, 2018 Contingent consideration, beginning of the year $ 4,698 $ 1,890 Additions for acquisitions 1,316 3,112 Reduction of liability for payments made (1,938 ) (728 ) Decrease (increase) of liability related to re-measurement of fair value (74 ) 424 Total contingent consideration, end of the period 4,002 4,698 Current portion of contingent consideration 1,954 1,845 Contingent consideration, less current portion $ 2,048 $ 2,853

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 28, 2019
Leases [Abstract]
Schedule of supplemental balance sheet information	Supplemental balance sheet information related to the Company's operating and finance leases is as follows: Leases Classification December 28, 2019 Assets Operating lease assets Right-of-use lease asset, net (1) $ 46,313 Finance lease assets Property and equipment, net (1) 2,371 Total leased assets $ 48,685 Liabilities Current Operating Accrued liabilities $ (13,108 ) Finance Current portion of notes payable and other obligations (1,022 ) Noncurrent Operating Long-term lease liability (34,573 ) Finance Notes payable and other obligations, less current portion (1,685 ) Total lease liabilities $ (50,388 ) (1) At December 28, 2019 , operating right of-use lease assets and finance lease assets are recorded net of accumulated amortization of $9,657 and $1,592 , respectively.
Schedule of lease term and discount rate	Supplemental balance sheet information related to the Company's operating and finance leases is as follows: Weighted - Average Remaining Lease Term (Years) December 28, 2019 Operating leases 5.0 Finance leases 2.8 Weighted - Average Discount Rate Operating leases 4% Finance leases 7%
Schedule of supplemental cash flow information	Supplemental cash flow information related to the Company's operating and finance lease liabilities is as follows: Fiscal Year Ended December 28, 2019 Operating cash flows from operating leases $ 10,988 Financing cash flows from finance leases $ 796 Right-of-use assets obtained in exchange for lease obligations Operating leases $ 20,731
Schedule of lease cost	The following table summarizes the components of lease cost recognized in the consolidated statements of net income and comprehensive income: Fiscal Year Ended Lease Cost Classification December 28, 2019 Operating lease cost Facilities and facilities related $ 11,538 Finance lease cost Amortization of right of use assets Depreciation and amortization 1,245 Interest on lease liabilities Interest expense 98 Total lease cost 12,881
Schedule of maturities of lease liabilities	Fiscal Year Operating Leases Finance Leases 2020 $ 14,620 $ 990 2021 12,492 875 2022 8,693 708 2023 6,205 438 2024 3,890 199 Thereafter 6,776 11 Total lease payments 52,676 3,221 Less: Interest (4,995 ) (514 ) Present value of lease liabilities $ 47,681 $ 2,707
Schedule of maturities of lease liabilities	As of December 28, 2019 , maturities of the Company's lease liabilities under its long-term operating leases and finance leases for the next five fiscal years and thereafter are as follows: Fiscal Year Operating Leases Finance Leases 2020 $ 14,620 $ 990 2021 12,492 875 2022 8,693 708 2023 6,205 438 2024 3,890 199 Thereafter 6,776 11 Total lease payments 52,676 3,221 Less: Interest (4,995 ) (514 ) Present value of lease liabilities $ 47,681 $ 2,707
Schedule of future minimum rental payments for operating leases	As of December 29, 2018 , future minimum payments by fiscal year for the Company's non-cancelable operating leases was as follows: Fiscal Year Amount 2019 $ 9,506 2020 8,054 2021 7,224 2022 5,364 2023 4,504 Thereafter 7,704 Total minimum lease payments $ 42,356

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 28, 2019
Share-based Payment Arrangement [Abstract]
Share-based payment arrangement, restricted stock unit, activity	The following summarizes the activity of restricted stock awards during fiscal years 2019 , 2018 and 2017 : Share Units Weighted Average Grant Date Fair Value Unvested shares as of December 31, 2016 502,773 $ 19.35 Granted 199,419 $ 38.72 Vested (93,805 ) $ 9.61 Forfeited (25,336 ) $ 28.79 Unvested shares as of December 30, 2017 583,051 $ 27.13 Granted 187,087 $ 65.15 Vested (127,870 ) $ 19.98 Forfeited (15,357 ) $ 32.14 Unvested shares as of December 29, 2018 626,911 $ 39.81 Granted 275,220 $ 70.90 Vested (207,039 ) $ 20.41 Forfeited (42,415 ) $ 53.24 Unvested shares as of December 28, 2019 652,677 $ 58.20

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 28, 2019
Income Tax Disclosure [Abstract]
Schedule of components of income tax expense (benefit)	Income tax expense for years 2019 , 2018 and 2017 consisted of the following: Years Ended December 28, 2019 December 29, 2018 December 30, 2017 Current: Federal $ 8,059 $ 7,261 $ 9,341 State 3,800 2,911 2,265 Foreign (49 ) 276 263 Total current income tax expense 11,810 10,448 11,869 Deferred: Federal (5,160 ) (2,924 ) (10,439 ) State (1,474 ) (661 ) (803 ) Total deferred income tax (benefit) (6,634 ) (3,585 ) (11,242 ) . Total income tax expense $ 5,176 $ 6,863 $ 627
Schedule of deferred tax assets and liabilities	Temporary differences comprising the net deferred income tax liability shown in the Company’s consolidated balance sheets were as follows: December 28, 2019 December 29, 2018 Deferred tax asset: Lease liabilities $ 17,651 $ — Tax carryforwards 7,767 — Accrued compensation 6,682 4,348 Allowance for doubtful accounts 1,789 1,044 Deferred rent — 201 Other 327 78 Total deferred tax asset $ 34,216 $ 5,671 Deferred tax liability: Acquired intangibles $ (60,045 ) $ (17,248 ) Right-of-use assets (17,189 ) — Depreciation and amortization (6,289 ) (2,444 ) Cash to accrual adjustment (2,569 ) (1,962 ) Other (1,465 ) (241 ) Total deferred tax liability (87,557 ) (21,895 ) Net deferred tax liability $ (53,341 ) $ (16,224 )
Schedule of effective income tax rate reconciliation	Total income tax expense was different than the amount computed by applying the Federal statutory rate as follows: Years Ended December 28, 2019 December 29, 2018 December 30, 2017 Tax at federal statutory rate $ 6,076 $ 7,081 $ 8,622 Stock based compensation (2,808 ) (1,014 ) (1,016 ) State taxes, net of Federal benefit 1,990 1,424 714 Federal and state tax credits (1,247 ) (923 ) (250 ) Changes in unrecognized tax position 425 111 506 Domestic production activities deduction — — (936 ) Transition tax — 110 357 Effect of change in income tax rate — 31 (6,249 ) Other 740 43 (1,121 ) Total income tax expense $ 5,176 $ 6,863 $ 627
Schedule of unrecognized tax benefits roll forward	A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows: December 28, 2019 December 29, 2018 December 30, 2017 Balance, beginning of period $ 548 $ 437 $ 770 Additions based on tax positions related to the current year 124 45 49 Additions for tax positions of prior years 338 66 525 Lapse of statute of limitations (123 ) — Reductions for positions of prior years — — (68 ) Settlement — — (839 ) Balance, end of period $ 887 $ 548 $ 437

Reportable Segments (Tables)

Reportable Segments (Tables)	12 Months Ended
	Dec. 28, 2019
Segment Reporting [Abstract]
Schedule of segment reporting information, by segment	The following tables set forth summarized financial information concerning our reportable segments: Years Ended December 28, 2019 December 29, 2018 December 30, 2017 Gross revenues INF $ 334,458 $ 257,353 $ 185,238 BTS 178,419 164,739 152,304 Elimination of inter- segment revenues (3,939 ) (4,011 ) (4,508 ) Total gross revenues $ 508,938 $ 418,081 $ 333,034 Segment income before taxes INF $ 54,583 $ 43,832 $ 32,245 BTS 28,138 26,656 21,018 Total Segment income before taxes 82,721 70,488 53,263 Corporate (1) (53,789 ) (36,769 ) (28,630 ) Total income before taxes $ 28,932 $ 33,719 $ 24,633 (1) Includes amortization of intangibles of $20,488 , $13,052 and $10,310 for the fiscal years ended 2019 , 2018 and 2017 , respectively. December 28, 2019 December 29, 2018 Assets INF $ 776,835 $ 228,979 BTS 23,976 155,112 Corporate (1) 92,326 55,330 Total assets $ 893,137 $ 439,421 (1) Corporate assets consist of intercompany eliminations and assets not allocated to segments including cash and cash equivalents and certain other assets.
Schedule of revenue from external customers by geographic areas	Gross revenue, classified by the major geographic areas in which our customers were located, were as follows: Fiscal Year Ended December 28, 2019 December 29, 2018 INF BTS Total INF BTS Total United States $ 331,161 $ 171,246 $ 502,407 $ 254,723 $ 150,696 $ 405,419 Foreign — 6,531 6,531 — 12,662 12,662 Total gross revenues $ 331,161 $ 177,777 $ 508,938 $ 254,723 $ 163,358 $ 418,081
Schedule of revenue by major customers by reporting segments	Gross revenue by customer were as follows: Fiscal Year Ended December 28, 2019 December 29, 2018 INF BTS Total INF BTS Total Public and quasi-public sector $ 271,935 $ 66,544 $ 338,479 $ 233,395 $ 45,393 $ 278,788 Private sector 59,226 111,233 170,459 21,328 117,965 139,293 Total gross revenues $ 331,161 $ 177,777 $ 508,938 $ 254,723 $ 163,358 $ 418,081
Schedule of revenue from external customers by products and services	Gross revenues by contract type were as follows: Fiscal Year Ended December 28, 2019 December 29, 2018 INF BTS Total INF BTS Total Cost-reimbursable contracts $ 318,112 $ 139,406 $ 457,518 $ 254,365 $ 128,738 $ 383,103 Fixed-unit price contracts 13,049 38,371 51,420 358 34,620 34,978 Total gross revenues $ 331,161 $ 177,777 $ 508,938 $ 254,723 $ 163,358 $ 418,081

Quarterly Financial Informati_2

Quarterly Financial Information (Unaudited) (Tables)	12 Months Ended
	Dec. 28, 2019
Quarterly Financial Information Disclosure [Abstract]
Schedule of quarterly information	Quarter Ended First Quarter Second Quarter Third Quarter Fourth Quarter Fiscal Year Ended December 28, 2019 Gross revenues $ 117,335 $ 127,974 $ 131,032 $ 132,598 Gross profit $ 55,430 $ 61,440 $ 63,496 $ 65,017 Income from operations $ 7,411 $ 9,597 $ 7,825 $ 6,374 Income before income tax expense $ 7,060 $ 9,140 $ 7,403 $ 5,329 Net income and comprehensive income $ 5,543 $ 8,794 $ 5,843 $ 3,575 Basic earnings per share $ 0.46 $ 0.73 $ 0.48 $ 0.29 Diluted earnings per share $ 0.44 $ 0.70 $ 0.46 $ 0.28 Quarter Ended First Quarter Second Quarter Third Quarter Fourth Quarter Fiscal Year Ended December 29, 2018 Gross revenues $ 94,534 $ 104,018 $ 104,185 $ 115,344 Gross profit $ 46,631 $ 50,702 $ 49,974 $ 54,097 Income from operations $ 6,301 $ 9,350 $ 9,974 $ 10,060 Income before income tax expense $ 5,690 $ 8,700 $ 9,523 $ 9,806 Net income and comprehensive income $ 4,292 $ 7,620 $ 7,285 $ 7,659 Basic earnings per share $ 0.42 $ 0.73 $ 0.65 $ 0.64 Diluted earnings per share $ 0.39 $ 0.69 $ 0.62 $ 0.62

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Product Information [Line Items]
Contract with customer liability	$ 7,625
Advertising expense	$ 939	$ 1,019	$ 1,048
Revenue benchmark | Government contracts concentration risk
Product Information [Line Items]
Concentration risk, percentage	68.00%	67.00%	68.00%
Revenue benchmark | Geographic concentration risk | CALIFORNIA
Product Information [Line Items]
Concentration risk, percentage	27.00%	30.00%	32.00%
Transferred at point in time
Product Information [Line Items]
Concentration risk, percentage	10.00%	8.00%

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Estimated Useful Lives of Property and Equipment (Details)	12 Months Ended
	Dec. 28, 2019
Office furniture and equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	4 years
Computer equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	3 years
Survey and field equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	5 years
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment, estimated useful lives	Lesser of the estimated useful lives or remaining term of the lease

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Revenue Recognition (Details) $ in Thousands	Dec. 28, 2019USD ($)
Accounting Policies [Abstract]
Revenue remaining performance obligation amount	$ 607,482
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-12-28
Accounting Policies [Abstract]
Revenue remaining performance obligation amount	$ 493,468
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue performance obligation expected timing of satisfaction period	24 months

Recent Issued Accounting Pron_2

Recent Issued Accounting Pronouncements - Recent Issued Accounting Pronouncements (Details Textual) - USD ($) $ in Thousands	Dec. 28, 2019	Jan. 01, 2019	Dec. 29, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Right-of-use lease assets, net	$ 46,313		$ 0
Present value of lease liabilities	$ 47,681
Accounting Standards Update 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Right-of-use lease assets, net		$ 34,186
Present value of lease liabilities		$ 34,965

Earnings per Share - Schedule o

Earnings per Share - Schedule of Earnings Per Share, Basic and Diluted (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 28, 2019	Sep. 28, 2019	Jun. 29, 2019	Mar. 30, 2019	Dec. 29, 2018	Sep. 29, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Numerator:
Net income – basic and diluted	$ 3,575	$ 5,843	$ 8,794	$ 5,543	$ 7,659	$ 7,285	$ 7,620	$ 4,292	$ 23,756	$ 26,856	$ 24,006
Denominator:
Basic weighted average shares outstanding									12,116,185	10,991,124	10,178,901
Effect of dilutive non-vested restricted shares and units									319,674	401,726	326,319
Effect of issuable shares related to acquisitions									77,175	87,713	157,965
Effect of warrants									0	25,903	114,621
Diluted weighted average shares outstanding									12,513,034	11,506,466	10,777,806

Earnings Per Share - Narrative

Earnings Per Share - Narrative (Details) - USD ($)	Aug. 13, 2018	Aug. 09, 2018	Mar. 21, 2018	Mar. 19, 2018	Mar. 23, 2016	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017	Mar. 26, 2013
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Proceeds from exercise of unit warrant						$ 0	$ 1,093,000	$ 0
Exercise price per warrant unit (in usd per share)									$ 7.80
Proceeds from issuance of common stock						$ 0	$ 100,330,000	$ 0
Follow-on offering | Firm shares
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Proceeds from secondary offering, net of costs (in shares)		1,270,000
Shares issued, price per share		$ 79
Underwriter | Follow-on offering | Firm shares
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Proceeds from issuance of common stock	$ 93,469
Underwriter | Follow-on offering | Share-based payment arrangement, option
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Proceeds from secondary offering, net of costs (in shares)		190,500
Unit warrant | Underwriter
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Warrant units (in shares)									140,000
Proceeds from exercise of unit warrant				$ 1,093	$ 1,008
Proceeds from exercise of warrants, net of costs (in shares)			140,000
Restricted Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Non-vested restricted shares						642,677	614,911	570,171

Stockholders' Equity (Details)

Stockholders' Equity (Details) - USD ($)	Aug. 13, 2018	Aug. 09, 2018	Mar. 21, 2018	Mar. 19, 2018	Mar. 23, 2016	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017	Mar. 26, 2013
Class of Stock [Line Items]
Proceeds from exercise of warrant						$ 0	$ 1,093,000	$ 0
Exercise price per warrant unit (in usd per share)									$ 7.80
Proceeds from common stock offering						$ 0	$ 100,330,000	$ 0
Unit warrant | Underwriter
Class of Stock [Line Items]
Warrant units (in shares)									140,000
Proceeds from exercise of warrant				$ 1,093	$ 1,008
Proceeds from exercise of warrants, net of costs (in shares)			140,000
Follow-on offering | Share-based payment arrangement, option | Underwriter
Class of Stock [Line Items]
Proceeds from secondary offering, net of costs (in shares)		190,500
Follow-on offering | Firm shares
Class of Stock [Line Items]
Proceeds from secondary offering, net of costs (in shares)		1,270,000
Shares issued, price per share		$ 79
Follow-on offering | Firm shares | Underwriter
Class of Stock [Line Items]
Proceeds from common stock offering	$ 93,469

Business Acquisitions - Narrati

Business Acquisitions - Narrative (Details)	Nov. 08, 2019USD ($)	Jul. 02, 2019USD ($)	Jul. 01, 2019USD ($)installmentsshares	Jun. 03, 2019USD ($)installmentsshares	Mar. 22, 2019USD ($)installments	Dec. 31, 2018USD ($)installmentsshares	Nov. 02, 2018USD ($)installmentsshares	Aug. 24, 2018USD ($)installmentsshares	Feb. 02, 2018USD ($)installmentsshares	Jan. 12, 2018USD ($)installmentsshares	Dec. 22, 2017USD ($)shares	Sep. 06, 2017USD ($)installmentsshares	Jun. 06, 2017USD ($)installmentsshares	May 04, 2017USD ($)installmentsshares	May 01, 2017USD ($)installmentsshares	Apr. 14, 2017USD ($)	Dec. 28, 2019USD ($)	Dec. 29, 2018USD ($)	Dec. 30, 2017USD ($)	Dec. 20, 2019USD ($)
Acquired Finite-Lived Intangible Assets [Line Items]
Payments to acquire businesses																	$ 1,202,000	$ 728,000	$ 563,000
Excess working capital																	8,781,000
Cash paid at closing																	6,677,000
Other commitment																	358,187,000	46,986,000		$ 150,000,000
Revolving commitments																				$ 215,000,000
Total consideration																	369,954,000	93,628,000
Earn-out of cash fair value																	4,002,000	4,698,000	1,890,000
Promissory note incurred																	1,004,000	3,112,000
Working capital adjustment reduction of purchase price																			2,360,000
Business combination, acquisition related costs																	1,492,000	1,267,000	$ 1,398,000
Uncollateralized promissory notes
Acquired Finite-Lived Intangible Assets [Line Items]
Other commitment																	36,217,000	40,001,000
AR Credit agreement
Acquired Finite-Lived Intangible Assets [Line Items]
Payments to acquire businesses																	318,000,000
Revolving commitments																	215,000,000
WHPacific, Inc.
Acquired Finite-Lived Intangible Assets [Line Items]
Total consideration		$ 9,000,000
GHD Services, Inc
Acquired Finite-Lived Intangible Assets [Line Items]
Total consideration	$ 8,300,000
GeoDesign, Inc
Acquired Finite-Lived Intangible Assets [Line Items]
Payments to acquire businesses			$ 8,500,000
Total consideration			12,800,000
Consideration transferred of common stock			$ 375,000
Common stock number of shares | shares			4,731
Common stock purchase price			$ 425,000
Earn-out of cash			1,500,000
Earn-out of cash fair value			198,000
GeoDesign, Inc | Uncollateralized promissory notes
Acquired Finite-Lived Intangible Assets [Line Items]
Notes Payable			$ 2,000,000														2,000,000
Promissory note interest rate			4.00%
Number of installments | installments			4
Periodic payment			$ 500,000
Alta Environmental, L.P
Acquired Finite-Lived Intangible Assets [Line Items]
Payments to acquire businesses				$ 4,000,000
Total consideration				6,500,000
Earn-out of cash				500,000
Earn-out of cash fair value				323,000
Alta Environmental, L.P | Uncollateralized promissory notes
Acquired Finite-Lived Intangible Assets [Line Items]
Notes Payable				$ 2,000,000
Promissory note interest rate				4.00%
Number of installments | installments				4
Periodic payment				$ 500,000
Page One consultants
Acquired Finite-Lived Intangible Assets [Line Items]
Payments to acquire businesses				2,000,000
Total consideration				3,900,000
Consideration transferred of common stock				$ 200,000
Common stock number of shares | shares				2,647
Common stock purchase price				$ 200,000
Earn-out of cash				500,000
Earn-out of cash fair value				$ 448,000
Page One consultants | Uncollateralized promissory notes
Acquired Finite-Lived Intangible Assets [Line Items]
Notes Payable																	1,000,000
Promissory note interest rate				3.00%
Number of installments | installments				3
Promissory note incurred				$ 1,000,000
Periodic payment				$ 333,000
Acquisition of The Sextant Group
Acquired Finite-Lived Intangible Assets [Line Items]
Payments to acquire businesses					$ 7,000,000
Total consideration					$ 11,000,000
Acquisition of The Sextant Group | Uncollateralized promissory notes
Acquired Finite-Lived Intangible Assets [Line Items]
Notes Payable																	3,140,000
Promissory note interest rate					4.00%
Number of installments | installments					4
Promissory note incurred					$ 4,000,000
Periodic payment					$ 1,000,000
Celtic Energy, Inc
Acquired Finite-Lived Intangible Assets [Line Items]
Payments to acquire businesses						$ 1,000,000
Total consideration						1,900,000
Consideration transferred of common stock						$ 200,000
Common stock number of shares | shares						3,227
Common stock purchase price						$ 200,000
Earn-out of cash						200,000
Earn-out of cash fair value						$ 181,000
Celtic Energy, Inc | Uncollateralized promissory notes
Acquired Finite-Lived Intangible Assets [Line Items]
Notes Payable																	300,000
Promissory note interest rate						3.00%
Number of installments | installments						3
Promissory note incurred						$ 300,000
Periodic payment						$ 100,000
CHI Engineering Inc.
Acquired Finite-Lived Intangible Assets [Line Items]
Payments to acquire businesses							$ 30,000,000
Consideration transferred of common stock							$ 3,000,000
Common stock number of shares | shares							36,729
Common stock purchase price							$ 3,000,000
Earn-out of cash							2,000,000
Earn-out of cash fair value							1,547,000
Periodic payment							$ 1,000,000
Liability interest rate							3.00%
CHI Engineering Inc. | Uncollateralized promissory notes
Acquired Finite-Lived Intangible Assets [Line Items]
Notes Payable																	11,250,000	15,000,000
Promissory note interest rate							3.00%
Number of installments | installments							4
Number of equal installments | installments							3
Promissory note incurred							$ 15,000,000
Periodic payment							3,750,000
CHI Engineering Inc. | Maximum
Acquired Finite-Lived Intangible Assets [Line Items]
Total consideration							$ 53,000,000
CALYX Engineers and Consultants Inc.
Acquired Finite-Lived Intangible Assets [Line Items]
Payments to acquire businesses								$ 25,000,000
Total consideration								34,000,000
Consideration transferred of common stock								$ 3,000,000
Common stock number of shares | shares								36,379
CALYX Engineers and Consultants Inc. | Uncollateralized promissory notes
Acquired Finite-Lived Intangible Assets [Line Items]
Notes Payable																	3,000,000	4,000,000
Promissory note interest rate								3.75%
Number of installments | installments								4
Promissory note incurred								$ 4,000,000
Periodic payment								1,000,000
CALYX Engineers and Consultants Inc. | Cash Payable Within 120 Days
Acquired Finite-Lived Intangible Assets [Line Items]
Promissory note incurred								$ 2,000,000
CSA (M&E) Ltd.
Acquired Finite-Lived Intangible Assets [Line Items]
Payments to acquire businesses									$ 2,000,000
Total consideration									4,200,000
Consideration transferred of common stock									$ 150,000
Number of equal installments | installments									2
Common stock number of shares | shares									2,993
Common stock purchase price									$ 250,000
Earn-out of cash									1,200,000
Earn-out of cash fair value									899,000
Periodic payment									125,000
Business combination, consideration transferred, liabilities incurred including earn-out amount									$ 1,200,000
CSA (M&E) Ltd. | Uncollateralized promissory notes
Acquired Finite-Lived Intangible Assets [Line Items]
Notes Payable																	450,000	600,000
Promissory note interest rate									3.00%
Number of installments | installments									4
Promissory note incurred									$ 600,000						$ 2,200,000
Periodic payment									$ 150,000
Butsko Utility Design, Inc.
Acquired Finite-Lived Intangible Assets [Line Items]
Payments to acquire businesses										$ 1,500,000
Total consideration										4,250,000
Consideration transferred of common stock										$ 300,000
Number of equal installments | installments										2
Common stock number of shares | shares										5,630
Common stock purchase price										$ 600,000
Earn-out of cash										850,000
Earn-out of cash fair value										666,000
Periodic payment										$ 300,000
Butsko Utility Design, Inc. | Uncollateralized promissory notes
Acquired Finite-Lived Intangible Assets [Line Items]
Notes Payable																	750,000	1,000,000
Promissory note interest rate										3.00%
Number of installments | installments										4
Promissory note incurred										$ 1,000,000
Periodic payment										$ 250,000
Skyscene LLC
Acquired Finite-Lived Intangible Assets [Line Items]
Payments to acquire businesses											$ 250,000
Total consideration											650,000
Consideration transferred of common stock											$ 400,000
Common stock number of shares | shares											7,434
Marron and Associates, Inc.
Acquired Finite-Lived Intangible Assets [Line Items]
Payments to acquire businesses												$ 400,000
Consideration transferred of common stock												$ 67,000
Common stock number of shares | shares												1,510
Common stock purchase price												$ 133,000
Business combination, consideration transferred, cash and equity interest issued and issuable												133,000
Marron and Associates, Inc. | Uncollateralized promissory notes
Acquired Finite-Lived Intangible Assets [Line Items]
Earn-out of cash fair value												$ 90,000
Marron and Associates, Inc. | Uncollateralized promissory notes
Acquired Finite-Lived Intangible Assets [Line Items]
Notes Payable																	100,000	200,000
Promissory note interest rate												3.00%
Number of installments | installments												3
Promissory note incurred												$ 300,000
Periodic payment												100,000
Marron and Associates, Inc. | Maximum
Acquired Finite-Lived Intangible Assets [Line Items]
Total consideration												$ 990,000
Richard D. Kimball Co., Inc.
Acquired Finite-Lived Intangible Assets [Line Items]
Payments to acquire businesses													$ 15,000,000
Consideration transferred of common stock													$ 667,000
Common stock number of shares | shares													18,072
Common stock purchase price													$ 1,333,000
Business combination, consideration transferred, cash and equity interest issued and issuable													$ 1,333,000
Richard D. Kimball Co., Inc. | Uncollateralized promissory notes
Acquired Finite-Lived Intangible Assets [Line Items]
Notes Payable																	2,750,000	4,125,000
Promissory note interest rate													3.00%
Number of installments | installments													4
Promissory note incurred													$ 5,500,000
Periodic payment													1,375,000
Richard D. Kimball Co., Inc. | Maximum
Acquired Finite-Lived Intangible Assets [Line Items]
Total consideration													$ 22,500,000
Holdrege & Kull, Consulting Engineers and Geologists
Acquired Finite-Lived Intangible Assets [Line Items]
Payments to acquire businesses														$ 1,000,000
Consideration transferred of common stock														$ 100,000
Common stock number of shares | shares														2,628
Earn-out of cash														$ 500,000
Earn-out of cash fair value														405,000
Periodic payment														125,000
Business combination, consideration transferred, liabilities incurred including earn-out amount														$ 500,000
Holdrege & Kull, Consulting Engineers and Geologists | Uncollateralized promissory notes
Acquired Finite-Lived Intangible Assets [Line Items]
Notes Payable																	300,000	450,000
Promissory note interest rate														3.00%
Number of installments | installments														4
Promissory note incurred														$ 600,000
Periodic payment														150,000
Holdrege & Kull, Consulting Engineers and Geologists | Maximum
Acquired Finite-Lived Intangible Assets [Line Items]
Total consideration														$ 2,200,000
Lochrane Engineering, Inc.
Acquired Finite-Lived Intangible Assets [Line Items]
Payments to acquire businesses															2,690,000
Consideration transferred of common stock															$ 17,000
Common stock number of shares | shares															441
Earn-out of cash															$ 550,000
Business combination, consideration transferred, cash and equity interest issued and issuable															$ 33,000
Lochrane Engineering, Inc. | Uncollateralized promissory notes
Acquired Finite-Lived Intangible Assets [Line Items]
Number of installments | installments															4
Lochrane Engineering, Inc. | Uncollateralized promissory notes
Acquired Finite-Lived Intangible Assets [Line Items]
Notes Payable																	825,000	$ 1,238,000
Promissory note interest rate															3.00%
Number of installments | installments															4
Earn-out of cash fair value															$ 413,000
Promissory note incurred															1,650,000
Business combination, consideration transferred, liabilities incurred including earn-out amount															2,200,000
Debt instrument, periodic payment including earnt-out amount, total															550,000
Lochrane Engineering, Inc. | Maximum
Acquired Finite-Lived Intangible Assets [Line Items]
Total consideration															$ 4,940,000
Bock & Clark Corporation
Acquired Finite-Lived Intangible Assets [Line Items]
Total consideration																$ 42,000,000
NV5 and QSI
Acquired Finite-Lived Intangible Assets [Line Items]
Business combination, acquisition related costs																	$ 19,099,000

Business Acquisitions - Summary

Business Acquisitions - Summary of the fair values of assets acquired and liabilities assumed (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018
Finite-Lived Intangible Assets [Line Items]
Cash	$ 6,969	$ 345
Billed and unbilled receivables, net	64,165	20,999
Right-of-use assets	6,131	0
Property and equipment	15,789	3,122
Prepaid expenses	3,609	589
Other assets	2,365	83
Total Assets	276,027	72,197
Liabilities	(32,022)	(11,589)
Deferred tax liabilities	(43,151)	(8,903)
Net assets acquired	200,854	51,705
Consideration paid (Cash, Notes and/or stock)	368,950	90,516
Contingent consideration (earn-out)	1,004	3,112
Total Consideration	369,954	93,628
Excess consideration over the amounts assigned to the net assets acquired (Goodwill)	169,100	41,923
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Intangible assets	75,132	32,267
Trade name
Finite-Lived Intangible Assets [Line Items]
Intangible assets	59,911	2,479
Customer backlog
Finite-Lived Intangible Assets [Line Items]
Intangible assets	8,198	8,007
Developed technology
Finite-Lived Intangible Assets [Line Items]
Intangible assets	32,944	0
Other
Finite-Lived Intangible Assets [Line Items]
Intangible assets	814	$ 4,306
QSI
Finite-Lived Intangible Assets [Line Items]
Cash	6,894
Billed and unbilled receivables, net	42,523
Right-of-use assets	6,131
Property and equipment	13,626
Prepaid expenses	2,612
Other assets	1,317
Total Assets	236,137
Liabilities	(23,698)
Deferred tax liabilities	(39,372)
Net assets acquired	173,067
Consideration paid (Cash, Notes and/or stock)	318,004
Contingent consideration (earn-out)	0
Total Consideration	318,004
Excess consideration over the amounts assigned to the net assets acquired (Goodwill)	144,937
QSI | Customer relationships
Finite-Lived Intangible Assets [Line Items]
Intangible assets	64,709
QSI | Trade name
Finite-Lived Intangible Assets [Line Items]
Intangible assets	58,546
QSI | Customer backlog
Finite-Lived Intangible Assets [Line Items]
Intangible assets	6,835
QSI | Developed technology
Finite-Lived Intangible Assets [Line Items]
Intangible assets	32,944
QSI | Other
Finite-Lived Intangible Assets [Line Items]
Intangible assets	0
Other
Finite-Lived Intangible Assets [Line Items]
Cash	75
Billed and unbilled receivables, net	21,642
Right-of-use assets	0
Property and equipment	2,163
Prepaid expenses	997
Other assets	1,048
Total Assets	39,890
Liabilities	(8,324)
Deferred tax liabilities	(3,779)
Net assets acquired	27,787
Consideration paid (Cash, Notes and/or stock)	50,946
Contingent consideration (earn-out)	1,004
Total Consideration	51,950
Excess consideration over the amounts assigned to the net assets acquired (Goodwill)	24,163
Other | Customer relationships
Finite-Lived Intangible Assets [Line Items]
Intangible assets	10,423
Other | Trade name
Finite-Lived Intangible Assets [Line Items]
Intangible assets	1,365
Other | Customer backlog
Finite-Lived Intangible Assets [Line Items]
Intangible assets	1,363
Other | Developed technology
Finite-Lived Intangible Assets [Line Items]
Intangible assets	0
Other | Other
Finite-Lived Intangible Assets [Line Items]
Intangible assets	$ 814

Business Acquisitions - Results

Business Acquisitions - Results of operations from any business acquired (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Business Combinations [Abstract]
Gross revenues	$ 42,127	$ 33,468	$ 59,048
Income before income taxes	$ 3,170	$ 6,677	$ 10,755

Business Acquisitions - Pro For

Business Acquisitions - Pro Forma Consolidated Results of Operations (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Business Combinations [Abstract]
Gross revenues	$ 677,109	$ 689,580	$ 430,805
Net income	$ 18,421	$ 22,633	$ 22,464
Basic earnings per share (in dollars per share)	$ 1.52	$ 2.05	$ 2.19
Diluted earnings per share (in dollars per share)	$ 1.47	$ 1.95	$ 2.07

Billed and Unbilled Receivabl_3

Billed and Unbilled Receivables - Summary of Billed and Unbilled Receivables (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018
Receivables [Abstract]
Billed receivables	$ 134,900	$ 101,482
Less: allowance for doubtful accounts	(3,860)	(3,158)
Billed receivables, net	131,041	98,324
Unbilled receivables	80,639	44,799
Less: allowance for doubtful accounts	(1,211)	(1,388)
Unbilled receivables, net	$ 79,428	$ 43,411

Billed and Unbilled Receivabl_4

Billed and Unbilled Receivables - Activity in the Allowance for Doubtful Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Receivables [Abstract]
Balance as of the beginning of the year	$ 4,546	$ 3,642
Provision for doubtful accounts	1,239	797	$ 586
Write-offs of uncollectible accounts	(714)	(301)
Other	0	408
Balance as of the end of the year	$ 5,071	$ 4,546	$ 3,642

Property and Equipment, Net - N

Property and Equipment, Net - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Property, Plant and Equipment [Abstract]
Depreciation, total	$ 5,327	$ 4,331	$ 2,818

Property and Equipment, Net (De

Property and Equipment, Net (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 45,333	$ 22,035
Accumulated depreciation	(19,600)	(10,358)
Property and equipment, net	25,733	11,677
Office furniture and equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	4,198	2,328
Computer equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	10,704	11,640
Survey and field equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	24,165	5,526
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 6,266	$ 2,541

Goodwill and Intangible Asset_2

Goodwill and Intangible Assets - Schedule of Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018
Goodwill [Roll Forward]
Beginning balance	$ 140,930	$ 98,899
Acquisitions	169,100	41,923
Disposed/Adjustments	(814)	108
Ending balance	309,216	140,930
INF
Goodwill [Roll Forward]
Beginning balance	69,255	28,675
Acquisitions	162,814	40,472
Disposed/Adjustments	(814)	108
Ending balance	231,255	69,255
BTS
Goodwill [Roll Forward]
Beginning balance	71,675	70,224
Acquisitions	6,286	1,451
Disposed/Adjustments	0	0
Ending balance	$ 77,961	$ 71,675

Goodwill and Intangible Asset_3

Goodwill and Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Goodwill [Line Items]
Goodwill	$ 9,574	$ 14,350
Working capital adjustment reduction of purchase price			$ 2,360
Deferred tax adjustment, addition to goodwill of acquisition	1,546
Goodwill, purchase accounting adjustments	(814)	108
Amortization expense	20,488	13,052	$ 10,310
INF
Goodwill [Line Items]
Goodwill, purchase accounting adjustments	$ (814)	$ 108

Goodwill and Intangible Asset_4

Goodwill and Intangible Assets - Schedule of Finite-Lived Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018
Finite-lived intangible assets:
Gross Carrying Amount	$ 252,851	$ 134,950
Accumulated Amortization	(55,436)	(35,194)
Net Amount	197,415	99,756
Indefinite-lived intangible assets:
Gross Carrying Amount	58,546	0
Total intangible assets, gross carrying amount	311,397	134,950
Total intangible assets, net amount	255,961	99,756
QSI trade name
Indefinite-lived intangible assets:
Gross Carrying Amount	58,546	0
Customer relationships
Finite-lived intangible assets:
Gross Carrying Amount	176,088	100,956
Accumulated Amortization	(29,198)	(18,724)
Net Amount	$ 146,890	$ 82,232
Customer relationships | Minimum
Indefinite-lived intangible assets:
Useful life	1 year	1 year
Customer relationships | Maximum
Indefinite-lived intangible assets:
Useful life	12 years	10 years
Trade name
Finite-lived intangible assets:
Gross Carrying Amount	$ 10,253	$ 8,888
Accumulated Amortization	(8,593)	(6,469)
Net Amount	$ 1,660	$ 2,419
Trade name | Minimum
Indefinite-lived intangible assets:
Useful life	1 year	1 year
Trade name | Maximum
Indefinite-lived intangible assets:
Useful life	3 years	3 years
Customer backlog
Finite-lived intangible assets:
Gross Carrying Amount	$ 24,198	$ 16,000
Accumulated Amortization	(12,435)	(6,730)
Net Amount	11,763	9,270
Favorable lease
Finite-lived intangible assets:
Gross Carrying Amount	0	552
Accumulated Amortization	0	(197)
Net Amount	$ 0	$ 355
Indefinite-lived intangible assets:
Useful life	9 years	9 years
Non-compete
Finite-lived intangible assets:
Gross Carrying Amount	$ 9,369	$ 8,554
Accumulated Amortization	(5,105)	(3,074)
Net Amount	$ 4,264	$ 5,480
Non-compete | Minimum
Indefinite-lived intangible assets:
Useful life	4 years	4 years
Non-compete | Maximum
Indefinite-lived intangible assets:
Useful life	5 years	5 years
Developed technology
Finite-lived intangible assets:
Gross Carrying Amount	$ 32,944	$ 0
Accumulated Amortization	(106)	0
Net Amount	$ 32,838	$ 0
Developed technology | Minimum
Indefinite-lived intangible assets:
Useful life	5 years
Developed technology | Maximum
Indefinite-lived intangible assets:
Useful life	7 years

Goodwill and Intangible Asset_5

Goodwill and Intangible Assets - Weighted Average Useful Lives of Intangible Assets (Details)	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Weighted Average Useful Life (Year)	10 years	10 years
Trade name
Finite-Lived Intangible Assets [Line Items]
Weighted Average Useful Life (Year)	2 years	1 year 9 months 18 days
Customer backlog
Finite-Lived Intangible Assets [Line Items]
Weighted Average Useful Life (Year)	3 years	1 year 9 months 18 days
Developed technology
Finite-Lived Intangible Assets [Line Items]
Weighted Average Useful Life (Year)	7 years	0 years
Non-compete
Finite-Lived Intangible Assets [Line Items]
Weighted Average Useful Life (Year)	4 years	4 years 1 month 6 days

Goodwill and Intangible Asset_6

Goodwill and Intangible Assets - Schedule of Future Estimated Aggregate Amortization Related to Finite-lived Intangible Assets (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
2020	$ 31,398
2021	26,901
2022	22,569
2023	21,450
2024	21,155
Thereafter	73,941
Total	$ 197,415	$ 99,756

Accrued Liabilities - Summary o

Accrued Liabilities - Summary of Accrued Liabilities (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018
Payables and Accruals [Abstract]
Current portion of lease liability	$ 13,108	$ 0
Accrued vacation	10,048	7,994
Payroll and related taxes	12,146	8,136
Benefits	4,637	1,598
Unrecognized tax benefits	887	548
Professional liability reserve	1,083	157
Deferred rent	0	779
Other	5,523	1,641
Total	$ 47,432	$ 20,853

Notes Payable and Other Oblig_3

Notes Payable and Other Obligations - Narrative (Details)	Dec. 20, 2019USD ($)	Jul. 01, 2019USD ($)installments	Jun. 03, 2019USD ($)installments	Mar. 22, 2019USD ($)installments	Dec. 31, 2018USD ($)installments	Nov. 02, 2018USD ($)installments	Aug. 24, 2018USD ($)installments	Feb. 02, 2018USD ($)installments	Jan. 12, 2018USD ($)installments	Sep. 06, 2017USD ($)installments	Jun. 06, 2017USD ($)installments	May 04, 2017USD ($)installments	May 01, 2017USD ($)installments	Dec. 06, 2016USD ($)installments	Nov. 30, 2016USD ($)installments	Oct. 26, 2016USD ($)installments	Sep. 12, 2016USD ($)installments	May 20, 2016USD ($)installments	Jul. 01, 2015USD ($)installments	Jan. 30, 2015USD ($)installments	Dec. 28, 2019USD ($)	Dec. 29, 2018USD ($)	Dec. 30, 2017USD ($)
Debt Instrument [Line Items]
Revolving commitments	$ 215,000,000
Long tem debt	150,000,000																				$ 358,187,000	$ 46,986,000
Line of Credit Facility	$ 100,000,000
Interest rate during period	5.00%
Interest rate in year 3	7.50%
Minimum fixed charge coverage ratio																					1.20
Debt issuance costs, net of amortization																					$ 4,078,000	0
Amortization of debt issuance costs																					131,000	0	$ 0
Contingent earn-out liability (Cash and stock)																					1,004,000	3,112,000
GeoDesign, Inc
Debt Instrument [Line Items]
Purchase price		$ 425,000
Outstanding balance																					382,000
Page One consultants
Debt Instrument [Line Items]
Purchase price			$ 200,000
Outstanding balance																					181,000
Celtic Energy, Inc
Debt Instrument [Line Items]
Purchase price					$ 200,000
Outstanding balance																					181,000
CHI Engineering Inc.
Debt Instrument [Line Items]
Purchase price						$ 3,000,000
Outstanding balance																					1,754,000
Number of equal installments | installments						3
CSA (M&E) Ltd.
Debt Instrument [Line Items]
Purchase price								$ 250,000
Outstanding balance																					111,000	222,000
Number of equal installments | installments								2
Butsko Utility Design, Inc.
Debt Instrument [Line Items]
Purchase price									$ 600,000
Outstanding balance																					267,000	534,000
Number of equal installments | installments									2
Marron and Associates, Inc.
Debt Instrument [Line Items]
Purchase price										$ 133,000
Outstanding balance																						55,000
Number of equal installments | installments										2
Richard D. Kimball Co., Inc.
Debt Instrument [Line Items]
Purchase price											$ 1,333,000
Outstanding balance																						504,000
Number of equal installments | installments											2
Dade Moeller
Debt Instrument [Line Items]
Purchase price																		$ 3,000,000
Outstanding balance																						936,000
Number of equal installments | installments																		3
Periodic payments																		$ 1,000,000
Senior credit facility
Debt Instrument [Line Items]
Long tem debt	$ 150,000,000																				320,457,000	0
AR Credit agreement
Debt Instrument [Line Items]
Payments of dividends																					10,000
Debt issuance costs, net of amortization																					3,676,000
Amortization of debt issuance costs																					131,000
Uncollateralized promissory notes
Debt Instrument [Line Items]
Long tem debt																					36,217,000	40,001,000
Uncollateralized promissory notes | GeoDesign, Inc
Debt Instrument [Line Items]
Promissory note interest rate		4.00%
Number of installments | installments		4
Notes payable outstanding balance		$ 2,000,000																			2,000,000
Uncollateralized promissory notes | Page One consultants
Debt Instrument [Line Items]
Contingent earn-out liability (Cash and stock)			$ 1,000,000
Promissory note interest rate			3.00%
Number of installments | installments			3
Notes payable outstanding balance																					1,000,000
Uncollateralized promissory notes | Celtic Energy, Inc
Debt Instrument [Line Items]
Contingent earn-out liability (Cash and stock)					$ 300,000
Promissory note interest rate					3.00%
Number of installments | installments					3
Notes payable outstanding balance																					300,000
Uncollateralized promissory notes | CHI Engineering Inc.
Debt Instrument [Line Items]
Contingent earn-out liability (Cash and stock)						$ 15,000,000
Promissory note interest rate						3.00%
Number of installments | installments						4
Notes payable outstanding balance																					11,250,000	15,000,000
Uncollateralized promissory notes | CSA (M&E) Ltd.
Debt Instrument [Line Items]
Contingent earn-out liability (Cash and stock)								$ 600,000					$ 2,200,000
Promissory note interest rate								3.00%
Periodic payments								$ 150,000
Number of installments | installments								4
Notes payable outstanding balance																					450,000	600,000
Uncollateralized promissory notes | Butsko Utility Design, Inc.
Debt Instrument [Line Items]
Contingent earn-out liability (Cash and stock)									$ 1,000,000
Promissory note interest rate									3.00%
Periodic payments									$ 250,000
Number of installments | installments									4
Notes payable outstanding balance																					750,000	1,000,000
Uncollateralized promissory notes | Marron and Associates, Inc.
Debt Instrument [Line Items]
Contingent earn-out liability (Cash and stock)										$ 300,000
Promissory note interest rate										3.00%
Periodic payments										$ 100,000
Number of installments | installments										3
Notes payable outstanding balance																					100,000	200,000
Uncollateralized promissory notes | Richard D. Kimball Co., Inc.
Debt Instrument [Line Items]
Contingent earn-out liability (Cash and stock)											$ 5,500,000
Promissory note interest rate											3.00%
Periodic payments											$ 1,375,000
Number of installments | installments											4
Notes payable outstanding balance																					2,750,000	4,125,000
Uncollateralized promissory notes | Dade Moeller
Debt Instrument [Line Items]
Contingent earn-out liability (Cash and stock)																		$ 6,000,000
Promissory note interest rate																		3.00%
Periodic payments																		$ 1,500,000
Number of installments | installments																		4
Notes payable outstanding balance																					1,497,000	3,036,000
Uncollateralized promissory notes | Alta Environmental, L.P
Debt Instrument [Line Items]
Outstanding balance																					2,000,000
Promissory note interest rate			4.00%
Number of installments | installments			4
Notes payable outstanding balance			$ 2,000,000
Uncollateralized promissory notes | Acquisition of The Sextant Group
Debt Instrument [Line Items]
Contingent earn-out liability (Cash and stock)				$ 4,000,000
Promissory note interest rate				4.00%
Number of installments | installments				4
Notes payable outstanding balance																					3,140,000
Uncollateralized promissory notes | CALYX Engineers and Consultants Inc.
Debt Instrument [Line Items]
Contingent earn-out liability (Cash and stock)							$ 4,000,000
Promissory note interest rate							3.75%
Periodic payments							$ 1,000,000
Number of installments | installments							4
Notes payable outstanding balance																					3,000,000	4,000,000
Uncollateralized promissory notes | Holdrege & Kull, Consulting Engineers and Geologists
Debt Instrument [Line Items]
Contingent earn-out liability (Cash and stock)												$ 600,000
Promissory note interest rate												3.00%
Periodic payments												$ 150,000
Number of installments | installments												4
Notes payable outstanding balance																					300,000	450,000
Uncollateralized promissory notes | Lochrane Engineering, Inc.
Debt Instrument [Line Items]
Contingent earn-out liability (Cash and stock)													$ 1,650,000
Promissory note interest rate													3.00%
Periodic payments													$ 413,000
Number of installments | installments													4
Notes payable outstanding balance																					825,000	1,238,000
Uncollateralized promissory notes | CivilSource, Inc.
Debt Instrument [Line Items]
Contingent earn-out liability (Cash and stock)														$ 3,500,000
Promissory note interest rate														3.00%
Periodic payments														$ 875,000
Number of installments | installments														4
Notes payable outstanding balance																					1,502,000	2,625,000
Uncollateralized promissory notes | The Hanna Group, Inc.
Debt Instrument [Line Items]
Contingent earn-out liability (Cash and stock)															$ 2,700,000
Promissory note interest rate															3.00%
Periodic payments															$ 675,000
Number of installments | installments															4
Notes payable outstanding balance																					675,000	1,350,000
Uncollateralized promissory notes | JBA Consulting Engineers, Inc.
Debt Instrument [Line Items]
Contingent earn-out liability (Cash and stock)																$ 7,000,000
Promissory note interest rate																3.00%
Periodic payments																$ 1,400,000
Number of installments | installments																5
Notes payable outstanding balance																					4,163,000	4,200,000
Uncollateralized promissory notes | Weir Environmental LLC
Debt Instrument [Line Items]
Contingent earn-out liability (Cash and stock)																	$ 500,000
Promissory note interest rate																	3.00%
Periodic payments																	$ 125,000
Number of installments | installments																	4
Notes payable outstanding balance																					125,000	250,000
Uncollateralized promissory notes | RBA Group Inc.
Debt Instrument [Line Items]
Contingent earn-out liability (Cash and stock)																			$ 4,000,000
Promissory note interest rate																			3.00%
Number of installments | installments																			4
Notes payable outstanding balance																						$ 1,000,000
Uncollateralized promissory notes | Joslin Lesser and Associates
Debt Instrument [Line Items]
Contingent earn-out liability (Cash and stock)																				$ 1,250,000
Promissory note interest rate																				3.50%
Periodic payments																				$ 313,000
Number of installments | installments																				4
Notes payable outstanding balance																					$ 313,000

Notes Payable and Other Oblig_4

Notes Payable and Other Obligations - Summary of notes payable and other obligations (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 20, 2019	Dec. 29, 2018
Debt Instrument [Line Items]
Notes payable and other obligations	$ (358,187)	$ (150,000)	$ (46,986)
Debt issuance costs, net of amortization	4,078		0
Current portion of notes payable and other obligations	(25,332)		(17,139)
Notes payable and other obligations, less current portion	332,854		29,847
Senior credit facility
Debt Instrument [Line Items]
Notes payable and other obligations	(320,457)	$ (150,000)	0
Uncollateralized promissory notes
Debt Instrument [Line Items]
Notes payable and other obligations	(36,217)		(40,001)
Finance leases
Debt Instrument [Line Items]
Notes payable and other obligations	(2,707)		(2,092)
Other obligations
Debt Instrument [Line Items]
Notes payable and other obligations	$ (2,884)		$ (4,893)

Notes Payable and Other Oblig_5

Notes Payable and Other Obligations - Future Contractual Maturities of Long-term Debt (Details) $ in Thousands	Dec. 28, 2019USD ($)
Payables and Accruals [Abstract]
2020	$ 26,039
2021	20,144
2022	19,400
2023	13,578
2024	283,104
Notes payable and other obligations	$ 362,265

Notes Payable and Other Oblig_6

Notes Payable and Other Obligations - Schedule of Consolidated Leverage Ratio (Details)	Dec. 28, 2019
Closing Date through June 30, 2020
Debt Instrument [Line Items]
Maximum consolidated leverage ratio	4.25
July 1, 2020 through September 30, 2020
Debt Instrument [Line Items]
Maximum consolidated leverage ratio	4
October 1, 2020 through December 31, 2020
Debt Instrument [Line Items]
Maximum consolidated leverage ratio	3.75
January 1, 2021 and thereafter
Debt Instrument [Line Items]
Maximum consolidated leverage ratio	3.5

Contingent Consideration - Summ

Contingent Consideration - Summary of Contingent Consideration (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018
Commitments and Contingencies Disclosure [Roll Forward]
Contingent consideration, beginning of the year	$ 4,698	$ 1,890
Additions for acquisitions	1,316	3,112
Reduction of liability for payments made	(1,938)	(728)
Decrease (increase) of liability related to re-measurement of fair value	(74)	424
Total contingent consideration, end of the period	4,002	4,698
Current portion of contingent consideration	(1,954)	(1,845)
Contingent consideration, less current portion	$ 2,048	$ 2,853

Leases - Schedule of supplement

Leases - Schedule of supplemental balance sheet information (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018
Assets
Operating lease assets	$ 46,313	$ 0
Total leased assets	48,685
Current
Operating	(13,108)	0
Noncurrent
Operating	(34,573)	$ 0
Total lease liabilities	(50,388)
Operating right of-use lease assets	9,657
Financing right of-use lease assets	1,592
Right-of-use lease asset, net
Assets
Operating lease assets	46,313
Property and equipment, net
Assets
Finance lease assets	2,371
Accrued liabilities
Current
Operating	(13,108)
Current portion of notes payable and other obligations
Current
Finance	(1,022)
Long-term lease liability
Noncurrent
Operating	(34,573)
Notes payable and other obligations, less current portion
Noncurrent
Finance	$ (1,685)

Leases - Schedule of lease term

Leases - Schedule of lease term and discount rate (Details)	Dec. 28, 2019
Weighted - Average Remaining Lease Term (Years)
Operating leases	5 years
Finance leases	2 years 9 months 18 days
Weighted - Average Discount Rate
Operating leases	4.00%
Finance leases	7.00%

Leases - Schedule of suppleme_2

Leases - Schedule of supplemental cash flow information (Details) $ in Thousands	12 Months Ended
	Dec. 28, 2019USD ($)
Supplemental Cash Flow Information
Operating cash flows from operating leases	$ 10,988
Financing cash flows from finance leases	796
Right-of-use assets obtained in exchange for lease obligations
Operating leases	$ 20,731

Leases - Schedule of lease cost

Leases - Schedule of lease cost (Details) $ in Thousands	12 Months Ended
	Dec. 28, 2019USD ($)
Lessee, Lease, Description [Line Items]
Total lease cost	$ 12,881
Facilities and facilities related
Lessee, Lease, Description [Line Items]
Operating lease cost	11,538
Depreciation and Amortization
Lessee, Lease, Description [Line Items]
Amortization of right of use assets	1,245
Interest expense
Lessee, Lease, Description [Line Items]
Interest on lease liabilities	$ 98

Leases - Schedule of maturities

Leases - Schedule of maturities of lease liabilities (Details) $ in Thousands	Dec. 28, 2019USD ($)
Operating Leases
2020	$ 14,620
2021	12,492
2022	8,693
2023	6,205
2024	3,890
Thereafter	6,776
Total lease payments	52,676
Less: Interest	(4,995)
Present value of lease liabilities	47,681
Finance Leases
2020	990
2021	875
2022	708
2023	438
2024	199
Thereafter	11
Total lease payments	3,221
Less: Interest	(514)
Present value of lease liabilities	$ 2,707

Leases - Future Minimum Payment

Leases - Future Minimum Payments (Details) $ in Thousands	Dec. 29, 2018USD ($)
Leases [Abstract]
2019	$ 9,506
2020	8,054
2021	7,224
2022	5,364
2023	4,504
Thereafter	7,704
Total minimum lease payments	$ 42,356

Stock-Based Compensation - Rest

Stock-Based Compensation - Restricted Stock Awards (Details) - Restricted Stock - $ / shares	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Number of Unvested Restricted Shares of Common Stock and Restricted Stock Units
Beginning (in shares)	626,911	583,051	502,773
Granted (in shares)	275,220	187,087	199,419
Vested (in shares)	(207,039)	(127,870)	(93,805)
Forfeited (in shares)	(42,415)	(15,357)	(25,336)
Ending (in shares)	652,677	626,911	583,051
Weighted Average Grant Date Fair Value
Beginning (in dollars per share)	$ 39.81	$ 27.13	$ 19.35
Granted (in dollars per share)	70.90	65.15	38.72
Vested (in dollars per share)	20.41	19.98	9.61
Forfeited (in dollars per share)	53.24	32.14	28.79
Ending (in dollars per share)	$ 58.20	$ 39.81	$ 27.13

Stock-Based Compensation - Narr

Stock-Based Compensation - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Deferred compensation	$ 10,430	$ 6,697	$ 4,011
Weighted average vesting period	$ 21,264
Vesting period	2 years
Fair value of restricted shares vested	$ 14,680	$ 7,422	$ 3,626
Equity Plan 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized	1,237,029
Rate of increase decrease in shares authorized for issuance	3.50%
Equity Plan 2011 | Minimum | Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	2 years
Equity Plan 2011 | Maximum | Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	4 years

Employee Benefit Plan - Narrati

Employee Benefit Plan - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Retirement Benefits [Abstract]
Defined contribution plan	$ 1,323	$ 676	$ 1,940

Income Taxes - Narrative (Detai

Income Taxes - Narrative (Details) - USD ($)	3 Months Ended	12 Months Ended
	Dec. 30, 2017	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Income Tax Examination [Line Items]
Deferred income tax liabilities, net		$ 53,341,000	$ 16,224,000
Deferred tax liabilities noncurrent		$ 43,151,000	$ 8,903,000
Effective income tax rate		35.00%	21.00%
Income tax expense (benefit)	$ (6,249,000)
Provisional liability transition tax	357,000			$ 357,000
Provisional liability transition tax adjustment amount	110,000			$ 110,000
Effective income tax rate percent		17.80%	20.40%	2.50%
Decrease resulting from settlements with taxing authorities		$ 0	$ 0	$ 839,000
Unrecognized tax benefits	437,000	887,000	548,000	$ 437,000	$ 770,000
Unrecognized tax benefits that would impact effective tax rate		769,000	$ 548,000
Income tax penalties and interest accrued		$ 204
State and Local Jurisdiction | California Franchise Tax Board
Income Tax Examination [Line Items]
Decrease resulting from settlements with taxing authorities	$ 839,000

Income Taxes - Income Tax Expen

Income Taxes - Income Tax Expense (Benefit) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Current:
Federal	$ 8,059	$ 7,261	$ 9,341
State	3,800	2,911	2,265
Foreign	(49)	276	263
Total current income tax expense	11,810	10,448	11,869
Deferred:
Federal	(5,160)	(2,924)	(10,439)
State	(1,474)	(661)	(803)
Total deferred income tax (benefit)	(6,634)	(3,585)	(11,242)
Total income tax expense	$ 5,176	$ 6,863	$ 627

Income Taxes - Net Deferred Inc

Income Taxes - Net Deferred Income Tax Asset (Liability) (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018
Deferred tax asset:
Lease liabilities	$ 17,651	$ 0
Tax carryforwards	7,767	0
Accrued compensation	6,682	4,348
Allowance for doubtful accounts	1,789	1,044
Deferred rent	0	201
Other	327	78
Total deferred tax asset	34,216	5,671
Deferred tax liability:
Acquired intangibles	(60,045)	(17,248)
Right-of-use assets	(17,189)	0
Depreciation and amortization	(6,289)	(2,444)
Cash to accrual adjustment	(2,569)	(1,962)
Other	(1,465)	(241)
Total deferred tax liability	(87,557)	(21,895)
Net deferred tax liability	$ (53,341)	$ (16,224)

Income Taxes - Income Tax Exp_2

Income Taxes - Income Tax Expense (Benefit) Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Income Tax Disclosure [Abstract]
Tax at federal statutory rate	$ 6,076	$ 7,081	$ 8,622
Stock based compensation	(2,808)	(1,014)	(1,016)
State taxes, net of Federal benefit	1,990	1,424	714
Federal and state tax credits	(1,247)	(923)	(250)
Changes in unrecognized tax position	425	111	506
Domestic production activities deduction	0	0	(936)
Transition tax	0	110	357
Effect of change in income tax rate	0	31	(6,249)
Other	740	43	(1,121)
Total income tax expense	$ 5,176	$ 6,863	$ 627

Income Taxes - Unrecognized Tax

Income Taxes - Unrecognized Tax Liability (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Income Tax Disclosure [Abstract]
Balance, beginning of period	$ 548	$ 437	$ 770
Additions based on tax positions related to the current year	124	45	49
Additions for tax positions of prior years	338	66	525
Lapse of statute of limitations	(123)		0
Reductions for positions of prior years	0	0	(68)
Settlement	0	0	(839)
Balance, end of period	$ 887	$ 548	$ 437

Reportable Segments - Narrative

Reportable Segments - Narrative (Details) $ in Thousands	12 Months Ended
	Dec. 28, 2019USD ($)operating_segmentsreportable_segments	Dec. 29, 2018USD ($)	Dec. 30, 2017USD ($)
Segment Reporting [Abstract]
Number of operating segments | operating_segments	2
Number of reportable segments | reportable_segments	2
Amortization expense | $	$ 20,488	$ 13,052	$ 10,310

Reportable Segments - Summarize

Reportable Segments - Summarized Financial Information (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 28, 2019	Sep. 28, 2019	Jun. 29, 2019	Mar. 30, 2019	Dec. 29, 2018	Sep. 29, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Segment Reporting, Revenue Reconciling Item [Line Items]
Gross revenues	$ 132,598	$ 131,032	$ 127,974	$ 117,335	$ 115,344	$ 104,185	$ 104,018	$ 94,534	$ 508,938	$ 418,081	$ 333,034
Segment income before taxes	5,329	$ 7,403	$ 9,140	$ 7,060	9,806	$ 9,523	$ 8,700	$ 5,690	28,932	33,719	24,633
Assets	893,137				439,421				893,137	439,421
INF
Segment Reporting, Revenue Reconciling Item [Line Items]
Gross revenues									331,161	254,723
BTS
Segment Reporting, Revenue Reconciling Item [Line Items]
Gross revenues									177,777	163,358
Operating Segments | INF
Segment Reporting, Revenue Reconciling Item [Line Items]
Gross revenues									334,458	257,353	185,238
Segment income before taxes									54,583	43,832	32,245
Assets	776,835				228,979				776,835	228,979
Operating Segments | BTS
Segment Reporting, Revenue Reconciling Item [Line Items]
Gross revenues									178,419	164,739	152,304
Segment income before taxes									28,138	26,656	21,018
Assets	23,976				155,112				23,976	155,112
Intersegment Eliminations
Segment Reporting, Revenue Reconciling Item [Line Items]
Gross revenues									(3,939)	(4,011)	(4,508)
Segment income before taxes									82,721	70,488	53,263
Corporate, Non-Segment
Segment Reporting, Revenue Reconciling Item [Line Items]
Segment income before taxes									(53,789)	(36,769)	$ (28,630)
Assets	$ 92,326				$ 55,330				$ 92,326	$ 55,330

Reportable Segments - Revenue b

Reportable Segments - Revenue by Geographic Location (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 28, 2019	Sep. 28, 2019	Jun. 29, 2019	Mar. 30, 2019	Dec. 29, 2018	Sep. 29, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Revenues from External Customers and Long-Lived Assets [Line Items]
Gross revenues	$ 132,598	$ 131,032	$ 127,974	$ 117,335	$ 115,344	$ 104,185	$ 104,018	$ 94,534	$ 508,938	$ 418,081	$ 333,034
INF
Revenues from External Customers and Long-Lived Assets [Line Items]
Gross revenues									331,161	254,723
BTS
Revenues from External Customers and Long-Lived Assets [Line Items]
Gross revenues									177,777	163,358
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Gross revenues									502,407	405,419
United States [Member] | INF
Revenues from External Customers and Long-Lived Assets [Line Items]
Gross revenues									331,161	254,723
United States [Member] | BTS
Revenues from External Customers and Long-Lived Assets [Line Items]
Gross revenues									171,246	150,696
Foreign [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Gross revenues									6,531	12,662
Foreign [Member] | INF
Revenues from External Customers and Long-Lived Assets [Line Items]
Gross revenues									0	0
Foreign [Member] | BTS
Revenues from External Customers and Long-Lived Assets [Line Items]
Gross revenues									$ 6,531	$ 12,662

Reportable Segments - Revenue_2

Reportable Segments - Revenue by Customer Type (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 28, 2019	Sep. 28, 2019	Jun. 29, 2019	Mar. 30, 2019	Dec. 29, 2018	Sep. 29, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Segment Reporting, Revenue Reconciling Item [Line Items]
Gross revenues	$ 132,598	$ 131,032	$ 127,974	$ 117,335	$ 115,344	$ 104,185	$ 104,018	$ 94,534	$ 508,938	$ 418,081	$ 333,034
INF
Segment Reporting, Revenue Reconciling Item [Line Items]
Gross revenues									331,161	254,723
BTS
Segment Reporting, Revenue Reconciling Item [Line Items]
Gross revenues									177,777	163,358
Public and quasi-public sector
Segment Reporting, Revenue Reconciling Item [Line Items]
Gross revenues									338,479	278,788
Public and quasi-public sector | INF
Segment Reporting, Revenue Reconciling Item [Line Items]
Gross revenues									271,935	233,395
Public and quasi-public sector | BTS
Segment Reporting, Revenue Reconciling Item [Line Items]
Gross revenues									66,544	45,393
Private sector
Segment Reporting, Revenue Reconciling Item [Line Items]
Gross revenues									170,459	139,293
Private sector | INF
Segment Reporting, Revenue Reconciling Item [Line Items]
Gross revenues									59,226	21,328
Private sector | BTS
Segment Reporting, Revenue Reconciling Item [Line Items]
Gross revenues									$ 111,233	$ 117,965

Reportable Segments - Revenue_3

Reportable Segments - Revenue by Contract Type (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 28, 2019	Sep. 28, 2019	Jun. 29, 2019	Mar. 30, 2019	Dec. 29, 2018	Sep. 29, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Segment Reporting, Revenue Reconciling Item [Line Items]
Gross revenues	$ 132,598	$ 131,032	$ 127,974	$ 117,335	$ 115,344	$ 104,185	$ 104,018	$ 94,534	$ 508,938	$ 418,081	$ 333,034
INF
Segment Reporting, Revenue Reconciling Item [Line Items]
Gross revenues									331,161	254,723
BTS
Segment Reporting, Revenue Reconciling Item [Line Items]
Gross revenues									177,777	163,358
Cost-reimbursable contracts
Segment Reporting, Revenue Reconciling Item [Line Items]
Gross revenues									457,518	383,103
Cost-reimbursable contracts | INF
Segment Reporting, Revenue Reconciling Item [Line Items]
Gross revenues									318,112	254,365
Cost-reimbursable contracts | BTS
Segment Reporting, Revenue Reconciling Item [Line Items]
Gross revenues									139,406	128,738
Fixed-unit price contracts
Segment Reporting, Revenue Reconciling Item [Line Items]
Gross revenues									51,420	34,978
Fixed-unit price contracts | INF
Segment Reporting, Revenue Reconciling Item [Line Items]
Gross revenues									13,049	358
Fixed-unit price contracts | BTS
Segment Reporting, Revenue Reconciling Item [Line Items]
Gross revenues									$ 38,371	$ 34,620

Quarterly Financial Informati_3

Quarterly Financial Information (Unaudited) - Quarterly Financial Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 28, 2019	Sep. 28, 2019	Jun. 29, 2019	Mar. 30, 2019	Dec. 29, 2018	Sep. 29, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Quarterly Financial Information Disclosure [Abstract]
Gross revenues	$ 132,598	$ 131,032	$ 127,974	$ 117,335	$ 115,344	$ 104,185	$ 104,018	$ 94,534	$ 508,938	$ 418,081	$ 333,034
Gross profit	65,017	63,496	61,440	55,430	54,097	49,974	50,702	46,631	245,382	201,404	165,254
Income from operations	6,374	7,825	9,597	7,411	10,060	9,974	9,350	6,301	31,207	35,685	26,568
Income before income tax expense	5,329	7,403	9,140	7,060	9,806	9,523	8,700	5,690	28,932	33,719	24,633
Net income and comprehensive income	$ 3,575	$ 5,843	$ 8,794	$ 5,543	$ 7,659	$ 7,285	$ 7,620	$ 4,292	$ 23,756	$ 26,856	$ 24,006
Basic earnings per share (in dollars per share)	$ 0.29	$ 0.48	$ 0.73	$ 0.46	$ 0.64	$ 0.65	$ 0.73	$ 0.42	$ 1.96	$ 2.44	$ 2.36
Diluted earnings per share (in dollars per share)	$ 0.28	$ 0.46	$ 0.70	$ 0.44	$ 0.62	$ 0.62	$ 0.69	$ 0.39	$ 1.90	$ 2.33	$ 2.23