Dorman Products (DORM) 10-Q 27 Apr 20 2020 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 28, 2020	Apr. 23, 2020
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 28, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q1
Trading Symbol	DORM
Title of 12(b) Security	Common stock, par value $0.01 per share
Security Exchange Name	NASDAQ
Entity Registrant Name	Dorman Products, Inc.
Entity Central Index Key	0000868780
Current Fiscal Year End Date	--12-26
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 File Number	0-18914
Entity Incorporation, State or Country Code	PA
Entity Tax Identification Number	23-2078856
Entity Address, Address Line One	3400 East Walnut Street
Entity Address, City or Town	Colmar
Entity Address, State or Province	PA
Entity Address, Postal Zip Code	18915
City Area Code	215
Local Phone Number	997-1800
Entity Common Stock, Shares Outstanding		32,443,271
Document Quarterly Report	true
Document Transition Report	false

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 28, 2020	Mar. 30, 2019
Income Statement [Abstract]
Net sales	$ 257,730	$ 243,791
Cost of goods sold	172,933	156,299
Gross profit	84,797	87,492
Selling, general and administrative expenses	59,735	57,750
Income from operations	25,062	29,742
Other income, net	2,631	29
Income before income taxes	27,693	29,771
Provision for income taxes	4,918	6,364
Net income	$ 22,775	$ 23,407
Earnings Per Share:
Basic	$ 0.70	$ 0.71
Diluted	$ 0.70	$ 0.71
Weighted Average Shares Outstanding:
Basic	32,354	32,801
Diluted	32,426	32,889

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 28, 2020	Dec. 28, 2019
Current assets:
Cash and cash equivalents	$ 161,778	$ 68,353
Accounts receivable, less allowance for doubtful accounts of $1,063 and $957	423,301	391,810
Inventories	258,371	280,813
Prepaids and other current assets	10,810	13,614
Total current assets	854,260	754,590
Property, plant and equipment, net	99,082	101,837
Operating lease right-of-use assets	32,230	32,198
Goodwill	91,275	74,458
Intangible assets, net	27,748	21,305
Deferred tax asset, net	3,886	4,336
Other assets	44,303	52,348
Total	1,152,784	1,041,072
Current liabilities:
Accounts payable	73,283	90,437
Accrued compensation	9,339	9,782
Accrued customer rebates and returns	110,374	105,903
Revolving credit line	99,000
Other accrued liabilities	22,541	14,380
Total current liabilities	314,537	220,502
Long-term operating lease liabilities	29,714	29,730
Other long-term liabilities	13,298	13,297
Deferred tax liabilities, net	3,860	3,959
Commitments and contingencies
Shareholders’ Equity:
Common stock, par value $0.01; authorized 50,000,000 shares; issued and outstanding 32,434,665 and 32,558,168 in 2020 and 2019, respectively	325	326
Additional paid-in capital	53,454	52,605
Retained earnings	737,596	720,653
Total shareholders’ equity	791,375	773,584
Total	$ 1,152,784	$ 1,041,072

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 28, 2020	Dec. 28, 2019
Statement Of Financial Position [Abstract]
Allowance for doubtful accounts and customer credits	$ 1,063	$ 957
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	50,000,000	50,000,000
Common stock, shares issued	32,434,665	32,558,168
Common stock, shares outstanding	32,434,665	32,558,168

Consolidated Statements of Shar

Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]
Beginning Balance at Dec. 29, 2018	$ 727,623	$ 330	$ 47,861	$ 679,432
Beginning Balance, Shares at Dec. 29, 2018		33,004,861
Exercise of stock options	31		31
Exercise of stock options, shares		11,714
Compensation expense under Incentive Stock Plan	915		915
Purchase and cancellation of common stock	(9,635)	$ (1)	(207)	(9,427)
Purchase and cancellation of common stock, Shares		(115,090)
Issuance of non-vested stock, net of cancellations, Shares		48,193
Other stock related activity, net of tax	(634)		1,290	(1,924)
Other stock related activity, net of tax, Shares		(7,665)
Net income	23,407			23,407
Ending Balance at Mar. 30, 2019	741,707	$ 329	49,890	691,488
Ending Balance, Shares at Mar. 30, 2019		32,942,013
Beginning Balance at Dec. 29, 2018	$ 727,623	$ 330	47,861	679,432
Beginning Balance, Shares at Dec. 29, 2018		33,004,861
Purchase and cancellation of common stock, Shares	(22,380)
Ending Balance at Dec. 28, 2019	$ 773,584	$ 326	52,605	720,653
Ending Balance, Shares at Dec. 28, 2019	32,558,168	32,556,263
Exercise of stock options, shares		10
Compensation expense under Incentive Stock Plan	$ 1,214		1,214
Purchase and cancellation of common stock	$ (5,780)	$ (1)	(175)	(5,604)
Purchase and cancellation of common stock, Shares	(4,730)	(96,709)
Issuance of non-vested stock, net of cancellations, Shares		(21,974)
Other stock related activity, net of tax	$ (418)		(190)	(228)
Other stock related activity, net of tax, Shares		(2,925)
Net income	22,775			22,775
Ending Balance at Mar. 28, 2020	$ 791,375	$ 325	$ 53,454	$ 737,596
Ending Balance, Shares at Mar. 28, 2020	32,434,665	32,434,665

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 28, 2020	Mar. 30, 2019
Cash Flows from Operating Activities:
Net income	$ 22,775	$ 23,407
Adjustments to reconcile net income to cash provided by operating activities:
Depreciation, amortization and accretion	7,496	7,265
Gain on equity method investment	(2,498)
Provision for doubtful accounts	14
Benefit for deferred income taxes	(912)
Provision for stock-based compensation	1,214	915
Changes in assets and liabilities:
Accounts receivable	(29,491)	13,333
Inventories	28,016	(18,184)
Prepaids and other current assets	2,262	(3,685)
Other assets	(2,219)	1,925
Accounts payable	(19,346)	(11,091)
Accrued customer rebates and returns	4,471	(497)
Accrued compensation and other liabilities	6,808	3,043
Cash provided by operating activities	18,590	16,431
Cash Flows from Investing Activities:
Acquisition, net of cash acquired	(14,462)
Property, plant and equipment additions	(3,505)	(8,838)
Cash used in investing activities	(17,967)	(8,838)
Cash Flows from Financing Activities:
Net proceeds of revolving credit line	99,000
Other stock related activity	(418)	(622)
Purchase and cancellation of common stock	(5,780)	(9,635)
Cash provided by (used in) financing activities	92,802	(10,257)
Net Increase (Decrease) in Cash and Cash Equivalents	93,425	(2,664)
Cash and Cash Equivalents, Beginning of Period	68,353	43,458
Cash and Cash Equivalents, End of Period	161,778	40,794
Supplemental Cash Flow Information
Cash paid for interest expense	20	61
Cash paid for income taxes	$ 62	$ 74

Basis of Presentation

Basis of Presentation	3 Months Ended
	Mar. 28, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Basis of Presentation	1. Basis of Presentation As used herein, unless the context otherwise requires, “Dorman,” the “Company,” “we,” “us,” or “our” refers to Dorman Products, Inc. and its subsidiaries. Our ticker symbol on the NASDAQ Global Select Market is “DORM.” The accompanying unaudited consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the U.S. for interim financial information and in accordance with the rules and regulations of the U.S. Securities and Exchange Commission (“SEC”). However, they do not include all the information and footnotes required by U.S. generally accepted accounting principles for complete financial statements. In the opinion of management, all adjustments (consisting of only normal recurring adjustments) considered necessary for a fair presentation have been included. Operating results for the thirteen weeks ended March 28, 2020 are not necessarily indicative of the results that may be expected for the fiscal year ending 2020 or any future period. We may experience significant fluctuations from quarter to quarter in our results of operations due to the timing of orders placed by our customers. The introduction of new products and product lines to customers may cause significant fluctuations from quarter to quarter. These financial statements should be read in conjunction with the consolidated financial statements and footnotes thereto included in our Annual Report on Form 10-K for the fiscal year ended December 28, 2019. Certain prior year amounts have been reclassified to conform with current year presentation. Revision of Prior Period Financial Statements During the quarter ended June 29, 2019, we identified and corrected an immaterial error that affected previously issued consolidated financial statements. This error related to the application of Financial Accounting Standards Board (“FASB”) Accounting Standards Update (“ASU”) No. 2014-09, Revenue from Contracts with Customers, Previously issued comparative financial statements, which were revised to correct the error noted above Thirteen Weeks Ended March 30, 2019 (in thousands) As Previously Reported Adjustment As Revised Revised Consolidated Statement of Cash Flows from Operating Activities Amounts: Accounts receivable $ 12,611 $ 722 $ 13,333 Accrued customer rebates and returns $ — $ (497 ) $ (497 ) Accrued compensation and other liabilities $ 3,268 $ (225 ) $ 3,043 Net cash provided by operating activities $ 16,431 $ — $ 16,431 Additionally, as a result of the adoption of ASU No. 2014-09, the Company should have disclosed the initial impact to the balance sheet reclassification for accrued customer rebates and returns from accounts receivable, net to accrued customer rebates and returns. The cumulative effect of the changes to the consolidated balance sheet from the adoption was as follows: (in thousands) As of December 30, 2017 Effect of Adoption As of December 31, 2017 Accounts receivable, net $ 241,880 $ 95,537 $ 337,417 Accrued customer rebates and returns $ 6,522 $ 95,537 $ 102,059 The correction of this error did not impact our Consolidated Statements of Operations or our Consolidated Statements of Shareholder’s Equity in any period presented.

Business Acquisitions and Inves

Business Acquisitions and Investments	3 Months Ended
	Mar. 28, 2020
Business Combinations [Abstract]
Business Acquisitions and Investments	2. Business Acquisitions and Investments Power Train Industries, Inc. On January 2, 2020, we acquired the remaining 60% of the outstanding stock of Power Train Industries, Inc. (“PTI”), a privately-held supplier of parts to the automotive aftermarket, based in Reno, Nevada. The total consideration paid for PTI was approximately $30.8 million, which included $18.0 million paid for the remaining 60% of the outstanding stock, $0.5 million deferred payment, subject to customary purchase price adjustments, and $12.3 million which represents the fair value of the previously held 40% equity interest in PTI that was acquired by the Company in 2016. As a result of the acquisition, we recorded a gain of approximately $2.5 million in Other Income in the thirteen weeks ended March 28, 2020, as a result of the increase in fair value of the previou sly owned 40% interest in PTI. We previously accounted for our 40% interest as an equity-method investment. The transaction was accounted for as a business combination under the acquisition method of accounting. Accordingly, the assets acquired, and liabilities assumed were recorded at fair value, with the remaining purchase price recorded as goodwill. In connection with this acquisition, we recorded $16.8 million in goodwill, $7.3 million of identified intangibles, and $6.7 million of other assets, net, primarily $3.5 million of cash, $2.0 million of accounts receivable, $5.6 million of inventory, The valuation of the intangible assets acquired and related amortization periods are as follows: (in thousands) Valuation Amortization Period (in years) Customer relationships $ 4,600 15 Tradenames 700 5 Technology 1,800 8 Other 190 5 Total $ 7,290 The fair values of the Customer relationships and Tradenames were estimated using a discounted present value income approach. The goodwill recognized is attributable primarily to strategic and synergistic opportunities related to existing automotive aftermarket businesses, the assembled workforce of PTI and other factors. The goodwill is not expected to be deductible for tax purposes. The financial results of the acquisition have been included in the Consolidated Financial Statements since the date of acquisition.

Sales of Accounts Receivable

Sales of Accounts Receivable	3 Months Ended
	Mar. 28, 2020
Receivables [Abstract]
Sales of Accounts Receivable	3. Sales of Accounts Receivable We have entered into several customer sponsored programs administered by unrelated financial institutions that permit us to sell certain accounts receivable at discounted rates to the financial institutions. Transactions under these agreements were accounted for as sales of accounts receivable and the related accounts receivable were removed from our Consolidated Balance Sheet at the time of the sales transactions. Pursuant to these agreements, we sold $151.3

Inventories

Inventories	3 Months Ended
	Mar. 28, 2020
Inventory Disclosure [Abstract]
Inventories	4. Inventories Inventories include the cost of material, freight, direct labor and overhead utilized in the processing of our products and are stated at the lower of cost or net realizable value. Inventories were as follows: (in thousands) March 28, 2020 December 28, 2019 Bulk product $ 101,118 $ 114,308 Finished product 152,632 161,866 Packaging materials 4,621 4,639 Total $ 258,371 $ 280,813

Leases

Leases	3 Months Ended
	Mar. 28, 2020
Leases [Abstract]
Leases	5 . Leases We adopted ASU No. 2016-02, Leases Operating leases are included in the right-of-use lease assets, other current liabilities and long-term lease liabilities on the Consolidated Balance Sheet. Right-of-use assets and lease liabilities are recognized at each lease’s commencement date based on the present values of its lease payments over its respective lease term. When a borrowing rate is not explicitly available for a lease, our incremental borrowing rate is used based on information available at the lease’s commencement date to determine the present value of its lease payments. Operating lease payments are recognized on a straight-line basis over t he lease term. We had no financing leases as of March 28, 2020 . We have operating leases for distribution centers, sales offices and certain warehouse and office equipment. Our leases have remaining lease terms of 1 to 11 years, many of which include one or more renewal options. We consider these renewal options in determining the lease term used to establish our right-of-use assets and lease liabilities when it is determined that it is reasonably certain that the renewal option will be exercised. As of March 28, 2020, there were no material variable lease costs or sublease income. Cash paid for operating leases was $1.9 million and $1.2 million in the thirteen weeks ended March 28, 2020 and March 30, 2019, respectively, which is classified in operating activities. The following table summarizes the lease expense for the thirteen weeks ended March 28, 2020 and March 30, 2019 (in thousands) March 28, 2020 March 30, 2019 Operating lease expense $ 1,901 $ 1,928 Short-term lease expense 1,114 1,070 Total lease expense $ 3,015 $ 2,998 Supplemental balance sheet information related to our operating leases is as follows: (in thousands) March 28, 2020 Operating lease right-of-use assets $ 32,230 Other accrued liabilities $ 5,412 Long-term operating lease liabilities 29,714 Total operating lease liabilities $ 35,126 Weighted average remaining lease term (years) 9.16 Weighted average discount rate 5.18 % The following table summarizes the maturities of our lease liabilities for all operating leases as of March 28, 2020: (in thousands) March 28, 2020 2020 (Remainder of 2020) $ 4,357 2021 5,476 2022 5,004 2023 3,388 2024 3,451 2025 and thereafter 21,514 Total lease payments 43,190 Less: Imputed interest (8,064 ) Present value of lease liabilities $ 35,126

Goodwill and Intangible Assets

Goodwill and Intangible Assets	3 Months Ended
	Mar. 28, 2020
Goodwill And Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	6 . Goodwill and Intangible Assets Goodwill Goodwill included the following: (in thousands) March 28, 2020 December 28, 2019 Balance at beginning of period $ 74,458 $ 72,606 Goodwill acquired 16,817 - Measurement period adjustments - 1,852 Balance at end of period $ 91,275 $ 74,458 Intangible Assets Intangible assets included the following: March 28, 2020 December 28, 2019 (in thousands) Weighted Average Amortization Period Gross Carrying Value Accumulated Amortization Net Carrying Value Gross Carrying Value Accumulated Amortization Net Carrying Value Intangible assets subject to amortization Tradenames 11.2 $ 6,760 $ 1,128 $ 5,632 $ 6,060 $ 975 $ 5,085 Customer relationships 9.3 25,050 5,310 19,740 20,450 4,698 $ 15,752 Technology 8.3 2,167 135 2,032 367 74 $ 293 Other 4.1 430 86 344 240 65 $ 175 Total $ 34,407 $ 6,659 $ 27,748 $ 27,117 $ 5,812 $ 21,305 Amortization expense was $0.8 million and $0.7 million for the thirteen weeks ended March 28, 2020 and March 30, 2019, respectively .

Debt

Debt	3 Months Ended
	Mar. 28, 2020
Debt Disclosure [Abstract]
Debt	7. Debt In December 2017, we entered into a credit agreement which will expire in December 2022. This agreement provides for an initial revolving credit facility of $100.0 million and, subject to certain requirements, gives us the ability to request increases of up to an incremental $100.0 million. The credit agreement replaced our previous $30.0 million facility. Borrowings under the credit agreement are on an unsecured basis. At the Company’s election, the interest rate applicable to borrowings under the credit agreement will be either (1) the Prime Rate as announced by Wells Fargo from time to time, (2) an Adjusted LIBOR Market Index Rate as measured by the LIBOR Market Index Rate plus the Applicable Margin which fluctuates between 65 basis points and 125 basis points based on the ratio of the Company’s Consolidated Funded Debt to Consolidated EBITDA, or (3) an Adjusted LIBOR Rate as measured by the LIBOR Rate plus the Applicable Margin which fluctuates between 65 basis points and 125 basis points based on the ratio of the Company’s Consolidated Funded Debt to Consolidated EBITDA. The interest rate at March 28, 2020 was LIBOR plus 65 basis points (1.64%). During the occurrence and continuance of an event of default, all outstanding revolving credit loans will bear interest at a rate per annum equal to 2.00% in excess of the greater of (1) the Prime Rate or (2) the Adjusted LIBOR Market Index Rate then applicable. As of March 28, 2020, we were not in default in respect to the credit agreement. The credit agreement also contains covenants, including those related to the ratio of certain consolidated fixed charges to consolidated EBITDA, capital expenditures, and share repurchases, each as defined by the credit agreement. The credit agreement also requires us to pay a fee of 0.10% on the average daily unused portion of the facility, provided the fee will not be charged on the first $30 million of the revolving credit facility. On March 23, 2020, Dorman took proactive steps to increase its cash position and preserve financial flexibility in light of uncertainties from the COVID-19 pandemic by drawing down $99.0 million from the revolving credit facility. See Note 17 for additional information regarding our response to COVID-19. As of March 28, 2020, we had $99.0 million in borrowings under the credit agreement, which amount does not include two outstanding letters of credit for approximately $0.8 million in the aggregate which were issued to secure ordinary course of business transactions. Net of these borrowings and letters of credit, we had approximately $0.2 million available under the credit agreement at March 28, 2020. In addition to the foregoing, and, subject to certain requirements, the credit agreement gives the Company the ability to request increases in revolving credit commitments of up to an additional $100.0 million. As of March 28, 2020, we were not in default in respect to the credit agreement.

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 28, 2020
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	8 . Commitments and Contingencies CBP Matter During 2019, we informed United States Customs & Border Protection (“CBP”) that we were commencing a voluntary disclosure process with CBP where we would voluntarily disclose to CBP certain product misclassifications and reimburse CBP for any resulting underpayment of duties that were identified as part of a voluntary internal review conducted by the Company. As of the date of this filing, our internal review is substantially complete. The Company recorded an estimated liability of $2.8 million in its Statement of Operations for the year ended December 28, 2019, which represents the Company’s estimated underpayment of duties, after deducting its estimated overpayment of duties, to CBP due to misclassifications over the prior five-year period, which is the applicable statute of limitations, plus applicable interest. The estimated liability of $2.8 million is reported in Other Long-Term Liabilities on the Consolidated Balance Sheet at March 28, 2020. The liability is reported in Other Long-Term liabilities since the ultimate resolution of the misclassifications with CBP is uncertain and is not expected to be resolved within the next twelve months. We expect to complete our internal review and make our initial prior disclosure submission to CBP in the first six months of 2020. However, the process of finalizing our prior disclosure with CBP may be iterative. We intend to work cooperatively with CBP in connection with the prior disclosure process and expect to complete the prior disclosure process with CBP and pay all required amounts within 18 months of our initial prior disclosure submission. Other Contingencies We are a party to or otherwise involved in legal proceedings that arise in the ordinary course of business, such as various claims and legal actions involving contracts, employment claims, competitive practices, intellectual property infringement, product liability claims and other matters arising out of the conduct of our business. In the opinion of management, none of the actions, individually or in the aggregate, taking into account relevant insurance coverage, would likely have a material financial impact on the Company and we believe the range of reasonably possible losses from current matters, taking into account relevant insurance coverage, is immaterial. However, legal matters are subject to inherent uncertainties and there exists the possibility that the ultimate resolution of any of these matters could have a material adverse impact on the Company’s cash flows, financial position and results of operations in the period in which any such effects are recorded.

Revenue Recognition

Revenue Recognition	3 Months Ended
	Mar. 28, 2020
Revenue From Contract With Customer [Abstract]
Revenue Recognition	9 . Revenue Recognition The FASB issued ASU No. 2014-09, Revenue from Contracts with Customers Our primary source of revenue is from contracts with and purchase orders from customers. Revenue is recognized from product sales when goods are shipped, title and risk of loss and control have been transferred to the customer, and collection is reasonably assured. We estimate the transaction price at the inception of a contract or upon fulfilling a purchase order, including any variable consideration, and will update the estimate for changes in circumstances. We utilize the most likely amount method consistently to estimate the effect of uncertainty on the amount of variable consideration to which we would be entitled. The most likely amount method considers the single most likely amount from a range of possible consideration amounts. This method is utilized for all of our variable consideration. We record estimates for cash discounts, product returns, promotional rebates, core (i.e. remanufactured parts) return deposits and other discounts in the period the related product revenue is recognized (“customer rebates and returns”). The provision for customer rebates and returns is recorded as a reduction of gross sales. Beginning with our Form 10-Q for the period ended June 29, 2019, our obligation associated with customer rebates and returns is classified as a current liability on our consolidated balance sheets (“accrued customer rebates and returns”). We have revised prior period balances to conform with this presentation. Please refer to Note 1. Actual customer rebates and returns have not differed materially from estimated amounts for each period presented. Amounts billed to customers for shipping and handling are included in net sales. Costs associated with shipping and handling are included in cost of goods sold. We have concluded that our estimates of variable consideration are not constrained according to the definition of the new standard. All of our revenue was recognized under the point of time approach in accordance with the revenue standard during the thirteen weeks ended March 28, 2020 and March 30, 2019, respectively. Also, we do not have significant financing arrangements with our customers, as our credit terms are all less than one year. Lastly, we do not receive noncash consideration (such as materials or equipment) from our customers to facilitate the fulfillment of our contracts. Five-step model We apply the FASB’s guidance on revenue recognition, which requires us to recognize the amount of revenue and consideration which we expect to receive in exchange for goods or services transferred to our customers. To do this, we apply the five-step model prescribed by the FASB, which requires us to: (i) identify the contract with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when, or as, we satisfy a performance obligation. Contract Assets and Liabilities We recognize a receivable or contract asset when we perform a service or transfer a good in advance of receiving consideration. - A receivable is recorded when our right to consideration is unconditional and only the passage of time is required before payment of that consideration is due. - A contract asset is recorded when our right to consideration in exchange for goods or services that we have transferred to a customer is conditional on something other than the passage of time. We did not have any contract assets recorded as of March 28, 2020 or December 28, 2019. We recognize a contract liability when we receive consideration, or if we have the unconditional right to receive consideration, in advance of satisfying the performance obligation. A contract liability is our obligation to transfer goods or services to a customer for which we have received consideration, or an amount of consideration is due from the customer. We did not have any contract liabilities recorded as of March 28, 2020 or December 28, 2019. Disaggregated Revenue The following tables present our disaggregated net sales by Type of Major Good / Product Line, and Geography. Thirteen Weeks Ended (in thousands) March 28, 2020 March 30, 2019 Powertrain $ 108,142 $ 95,163 Chassis 73,375 77,406 Automotive body 64,632 60,746 Hardware 11,581 10,476 Net sales $ 257,730 $ 243,791 Thirteen Weeks Ended (in thousands) March 28, 2020 March 30, 2019 Net sales to U.S. customers $ 241,392 $ 227,151 Net sales to non-U.S. customers $ 16,338 16,640 Net sales $ 257,730 $ 243,791

Stock-Based Compensation

Stock-Based Compensation	3 Months Ended
	Mar. 28, 2020
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-Based Compensation	10. Stock-Based Compensation On May 16, 2018, our shareholders approved our 2018 Stock Option and Stock Incentive Plan (the “2018 Plan”), which supersedes our 2008 Stock Option and Stock Incentive Plan (the “2008 Plan”). Under the terms of the 2018 Plan, our Board of Directors may grant up to 1,200,000 shares of common stock in the form of shares of restricted stock, restricted stock units, stock appreciation rights, stock options, or combinations thereof, to officers, directors, employees, consultants and advisors. Grants under the 2018 Plan must be made within ten years of the date the Plan was approved. Stock options are exercisable upon the terms set forth in each grant agreement, but in no event more than ten years from the date of grant. Restricted stock and restricted stock units vest in accordance with the terms set forth in each applicable award agreement. At March 28, 2020, 885,847 shares were available for grant under the 2018 Plan. Restricted Stock and Restricted Stock Units (“RSUs”) Vesting of restricted stock and RSU awards is conditional based on continued employment or service for a specified period and, in certain circumstances, the attainment of performance goals. With respect to restricted stock and RSU awards, we retain the shares underlying the award, and any dividends paid thereon, until the vesting conditions have been met. For time-based restricted stock and RSU awards, compensation cost related to the stock is recognized on a straight-line basis over the vesting period and is calculated using the closing price per share of our common stock on the grant date. For performance-based restricted stock and RSU awards tied to growth in adjusted pre-tax income, compensation cost related to the award is recognized over the performance period and is calculated using the closing price per share of our common stock on the grant date and an estimate of the probable outcome of the performance conditions at each reporting date. Since 2019, we have granted performance-based restricted stock and RSU awards that vest based on our total shareholder return ranking relative to the S&P Mid-Cap 400 Growth Index over a three-year performance period. For performance-based restricted stock and RSU awards tied to total shareholder return, compensation cost related to the award is recognized on a straight-line basis over the performance period and is calculated using the simulated fair value per share of our common stock based on the application of a Monte Carlo simulation model. Compensation cost related to restricted stock and RSU awards was $1.0 million and $0.7 million for the thirteen weeks ended March 28, 2020 and March 30, 2019 respectively, and is classified as selling, general and administrative expense in the Consolidated Statements of Operations. The following table summarizes our restricted stock and RSU award activity for the thirteen weeks ended March 28, 2020: Shares Weighted Average Price Balance at December 28, 2019 177,491 $ 76.70 Granted 72,369 $ 61.68 Vested (14,399 ) $ 65.13 Cancelled (22,488 ) $ 78.67 Balance at March 28, 2020 212,973 $ 72.17 As of March 28, 2020, there was $10.3 million of unrecognized compensation cost related to unvested restricted stock and RSU awards that is expected to be recognized over a weighted-average period of approximately 2.8 years. Cash flows resulting from tax deductions in excess of the tax effect of compensation cost recognized in the financial statements are classified as operating cash flows. The excess tax benefit generated from restricted stock and RSU awards that vested was $0.1 million and $0.2 million in the thirteen weeks ended March 28, 2020 and March 30, 2019, respectively, and was credited to income tax expense. Stock Options We expense the grant-date fair value of stock options. Compensation cost is recognized on a straight-line basis over the vesting period for which related services are performed. The compensation cost charged against income was $0.2 million for each of the thirteen weeks ended March 28, 2020 and March 30, 2019. The compensation costs were classified as selling, general and administrative expense in the Consolidated Statements of Operations. No cost was capitalized during the thirteen weeks ended March 28, 2020. We use the Black-Scholes option valuation model to estimate the fair value of stock options granted. Expected volatility and expected dividend yield are based on the actual historical experience of our common stock. The expected life represents the period of time that options granted are expected to be outstanding and was calculated using historical option exercise data. The risk-free rate was based on a U.S. Treasury security with terms equal to the expected time of exercise as of the grant date. During the thirteen weeks ended March 28, 2020 and March 30, 2019, we granted 98,974 and 28,538 stock options, respectively. The following table summarizes our stock option activity for the thirteen weeks ended March 28, 2020: Shares Weighted Average Exercise Price Weighted Average Remaining Term (In years) Aggregate Intrinsic Value Balance at December 28, 2019 181,712 $ 70.78 Granted 98,974 $ 61.86 Exercised (419 ) $ 72.55 Balance at March 28, 2020 280,267 $ 67.63 5.1 $ 265,750 Options exercisable at March 28, 2020 96,386 $ 65.15 2.4 $ 265,750 There were options to purchase 419 shares of common stock exercised during the thirteen weeks ended March 28, 2020. There were options to purchase 33,228 shares of common stock exercised during the thirteen weeks ended March 30, 2019. As of March 28, 2020, there was $4.0 million of unrecognized compensation cost related to unvested stock options that is expected to be recognized over a weighted-average period of 3.3 years. Cash generated from stock option exercises was-less than $0.1 million in each of the thirteen weeks ended March 28, 2020 and March 30, 2019. There was no excess tax benefit generated from stock options exercised in the thirteen weeks ended March 28, 2020 or March 30, 2019. Employee Stock Purchase Plan In May 2017, our shareholders approved the Dorman Products, Inc. Employee Stock Purchase Plan (the “ESPP”), which made available up to 1,000,000 shares of our common stock for sale to eligible employees. The purpose of the ESPP, which is qualified under Section 423 of the Internal Revenue Service Code of 1986, as amended, is to encourage stock ownership through payroll deductions and limited cash contributions by our employees. These contributions are used to purchase shares of the Company’s common stock at a 15% discount from the lower of the market price at the beginning or end of the purchase window. There were no

Earnings Per Share

Earnings Per Share	3 Months Ended
	Mar. 28, 2020
Earnings Per Share [Abstract]
Earnings Per Share	1 1 . Earnings Per Share Basic earnings per share is calculated by dividing our net income by the weighted average number of common shares outstanding during the period, excluding unvested restricted stock and shares of our common stock underlying RSUs and stock options that are considered to be contingently issuable. To calculate diluted earnings per share, common share equivalents are added to the weighted average number of common shares outstanding. Common share equivalents are calculated using the treasury stock method and are computed based on outstanding stock-based awards. Stock-based awards of 91,273 shares and 114,000 shares were excluded from the calculation of diluted earnings per share as of March 28, 2020 and March 30, 2019, respectively, as their effect would have been anti-dilutive. The following table sets forth the computation of basic earnings per share and diluted earnings per share: Thirteen Weeks Ended (in thousands, except per share data) March 28, 2020 March 30, 2019 Numerator Net income $ 22,775 $ 23,407 Denominator: Weighted average basic shares outstanding 32,354 32,801 Effect of stock-based compensation awards 72 88 Weighted average diluted shares outstanding 32,426 32,889 Earnings Per Share: Basic $ 0.70 $ 0.71 Diluted $ 0.70 $ 0.71

Common Stock Repurchases

Common Stock Repurchases	3 Months Ended
	Mar. 28, 2020
Text Block [Abstract]
Common Stock Repurchases	1 2 . Common Stock Repurchases We periodically repurchase, at the then current market price, and cancel shares of Dorman common stock issued to the Dorman Products, Inc. 401(k) Retirement Plan and Trust (the “401(k) Plan”). 401(k) Plan participants can no longer purchase shares of Dorman common stock as an investment option under the 401(k) Plan. Shares are generally purchased from the 401(k) Plan when participants sell units as permitted by the 401(k) Plan or elect to leave the 401(k) Plan upon retirement, termination or other reasons. For the thirteen weeks ended March 28, 2020, we repurchased and cancelled 4,730 shares of common stock held in the 401(k) Plan for $0.3 million at an average price of $66.66 per share. During the fifty-two weeks ended December 28, 2019, we repurchased and cancelled 22,380 shares of common stock held in the 401(k) Plan for $1.9 million at an average price of $87.26 per share. Our Board of Directors authorized a share repurchase program of up to $400 million through December 31, 2020. Under this program, share repurchases may be made from time to time depending on market conditions, share price, share availability and other factors at our discretion. The share repurchase program does not obligate us to acquire any specific number of shares. For the thirteen weeks ended March 28, 2020, we repurchased and cancelled 91,979 shares of common stock for $5.5 million at an average price of $59.41 per share under this program. For the fifty-two weeks ended December 28, 2019, we repurchased and cancelled 499,564 shares of common stock for $39.4 million at an average price of $78.84 per share under this program.

Related-Party Transactions

Related-Party Transactions	3 Months Ended
	Mar. 28, 2020
Related Party Transactions [Abstract]
Related-Party Transactions	1 3 . Related-Party Transactions We have a non-cancelable operating lease for our primary operating facility with a partnership in which Steven L. Berman, our Executive Chairman, and other members of the Berman family, are partners. Based upon the terms of the lease, payments will be $1.6 million in fiscal 2020 and We also have non-cancelable operating leases with a limited liability company in which certain of the former owners of PTI are members. The leases were entered into prior to the January 2, 2020 acquisition of PTI by the Company, and they are used in the PTI business. Based upon the terms of the leases, aggregate payments thereunder will be $0.3 million in fiscal 2020 Additionally, we had a non-cancelable operating lease for our Canadian operating facility from a corporation of which an employee, who is also the former owner of an acquired entity, and his family members are owners. Based upon the terms of the lease, payments were $0.2 million in fiscal We are a partner in a joint venture with one of our suppliers and own minority interests in two other suppliers. Each of these investments is accounted for according to the equity method.

Income Taxes

Income Taxes	3 Months Ended
	Mar. 28, 2020
Income Tax Disclosure [Abstract]
Income Taxes	1 4 . Income Taxes At March 28, 2020, we had $2.3 million of net unrecognized tax benefits, $2.0 million of which would lower our effective tax rate if recognized. We recognize interest and penalties related to uncertain tax positions in income tax expense. As of March 28, 2020 we had approximately $0.4 million of accrued interest and penalties related to uncertain tax positions. We file income tax returns in the United States, Canada, China, India, and Mexico. All years before 2016 are closed for United States federal tax purposes. Tax years before 2015 are closed for the states in which we file. Tax years before 2016 are closed for tax purposes in Canada. Tax years before 2015 are closed for tax purposes in China. All tax years remain open for Mexico and India.

Fair Value Disclosures

Fair Value Disclosures	3 Months Ended
	Mar. 28, 2020
Fair Value Disclosures [Abstract]
Fair Value Disclosures	15. Fair Value Disclosures The carrying value of financial instruments such as cash, accounts receivable, accounts payable, and other current assets and liabilities approximate their fair value based on the short-term nature of these instruments.

New and Recently Adopted Accoun

New and Recently Adopted Accounting Pronouncements	3 Months Ended
	Mar. 28, 2020
Accounting Changes And Error Corrections [Abstract]
New and Recently Adopted Accounting Pronouncements	1 6 . New and Recently Adopted Accounting Pronouncements In January 2017, the FASB issued ASU 2017-04, Simplifying the Test for Goodwill Impairment In June 2016, the FASB issued ASU 2016-13 , Financial Instruments – Credit Losses In December 2019, the FASB issued ASU 2019-12, Income Taxes (Topic740): Simplifying the Accounting for Income Taxes interim periods. The ASU also adds guidance to reduce complexity in certain areas, including recognizing deferred taxes for tax goodwill and allocating taxes to members of a consolidated group. ASU 2019-12 is effective for companies beginning with fiscal years beginning after December 15, 2020. The Company is currently evaluating the new guidance to determine the impact the adoption of this guidance will have on the Company’s results of operations, cash flows, and financial condition. However, at this time we do not believe this new guidance will have a material impact on our consolidated financial statements and related disclosures. In January 2020, the FASB issued ASU 2020-01, Investments – Equity Securities (Topic 321), Investments – Equity Method and Joint Ventures (Topic 323), and Derivatives and Hedging (Topic 815): Clarifying the Interactions between Topic 321, Topic 323 and Topic 815 In March 2020, the FASB issued ASU 2020-04, Reference Rate Reform (Topic 848):Facilitation of the Effects of Reference Rate Reform on Financial Reporting,

Subsequent Events

Subsequent Events	3 Months Ended
	Mar. 28, 2020
Subsequent Events [Abstract]
Subsequent Events	17. Subsequent Events The recent outbreak of the novel coronavirus COVID-19, which was declared a pandemic by the World Health Organization on March 11, 2020, has led to adverse impacts on the U.S. and global economies and created uncertainty regarding potential impacts to the Company’s employees, supply chain, operations, and customer demand. The COVID-19 pandemic has impacted and could further impact the Company’s operations and the operations of the Company’s customers, suppliers and vendors as a result of quarantines, facility closures, and travel and logistics restrictions. The extent to which the COVID-19 pandemic impacts the Company’s business, results of operations and financial condition will depend on future developments, which are highly uncertain and cannot be predicted, including, but not limited to the duration, spread, severity, and impact of the COVID-19 pandemic, the effects of the COVID-19 pandemic on the Company’s customers, suppliers, and vendors and the remedial actions and stimulus measures adopted by local, state and federal governments, and to what extent normal economic and operating conditions can resume. Even after the COVID-19 pandemic has subsided, the Company may continue to experience adverse impacts to its business as a result of any economic recession or depression that has occurred or may occur in the future. Therefore, the Company cannot reasonably estimate the impact at this time. In light of the COVID-19 pandemic, the Company has taken proactive steps to manage its costs and bolster its liquidity, including increasing the level of receivables collected under various factoring programs. Since the end of the first quarter of 2020 through April 24, 2020, the Company factored $192.0 million of receivables under these programs, with $3.7 million in financing costs associated with these accounts receivable sales.

New and Recently Adopted Acco_2

New and Recently Adopted Accounting Pronouncements (Policies)	3 Months Ended
	Mar. 28, 2020
Accounting Changes And Error Corrections [Abstract]
New and Recently Adopted Accounting Pronouncements	In January 2017, the FASB issued ASU 2017-04, Simplifying the Test for Goodwill Impairment In June 2016, the FASB issued ASU 2016-13 , Financial Instruments – Credit Losses In December 2019, the FASB issued ASU 2019-12, Income Taxes (Topic740): Simplifying the Accounting for Income Taxes interim periods. The ASU also adds guidance to reduce complexity in certain areas, including recognizing deferred taxes for tax goodwill and allocating taxes to members of a consolidated group. ASU 2019-12 is effective for companies beginning with fiscal years beginning after December 15, 2020. The Company is currently evaluating the new guidance to determine the impact the adoption of this guidance will have on the Company’s results of operations, cash flows, and financial condition. However, at this time we do not believe this new guidance will have a material impact on our consolidated financial statements and related disclosures. In January 2020, the FASB issued ASU 2020-01, Investments – Equity Securities (Topic 321), Investments – Equity Method and Joint Ventures (Topic 323), and Derivatives and Hedging (Topic 815): Clarifying the Interactions between Topic 321, Topic 323 and Topic 815 In March 2020, the FASB issued ASU 2020-04, Reference Rate Reform (Topic 848):Facilitation of the Effects of Reference Rate Reform on Financial Reporting,

Basis of Presentation (Tables)

Basis of Presentation (Tables)	3 Months Ended
	Mar. 28, 2020
ASU 2014-09 [Member]
Schedule of Revision of Prior Period Financial Statements	Previously issued comparative financial statements, which were revised to correct the error noted above Thirteen Weeks Ended March 30, 2019 (in thousands) As Previously Reported Adjustment As Revised Revised Consolidated Statement of Cash Flows from Operating Activities Amounts: Accounts receivable $ 12,611 $ 722 $ 13,333 Accrued customer rebates and returns $ — $ (497 ) $ (497 ) Accrued compensation and other liabilities $ 3,268 $ (225 ) $ 3,043 Net cash provided by operating activities $ 16,431 $ — $ 16,431 Additionally, as a result of the adoption of ASU No. 2014-09, the Company should have disclosed the initial impact to the balance sheet reclassification for accrued customer rebates and returns from accounts receivable, net to accrued customer rebates and returns. The cumulative effect of the changes to the consolidated balance sheet from the adoption was as follows: (in thousands) As of December 30, 2017 Effect of Adoption As of December 31, 2017 Accounts receivable, net $ 241,880 $ 95,537 $ 337,417 Accrued customer rebates and returns $ 6,522 $ 95,537 $ 102,059

Business Acquisitions and Inv_2

Business Acquisitions and Investments (Tables)	3 Months Ended
	Mar. 28, 2020
Power Train Industries, Inc. [Member]
Schedule of Valuation of Intangible Assets Acquired and Related Amortization Periods	The valuation of the intangible assets acquired and related amortization periods are as follows: (in thousands) Valuation Amortization Period (in years) Customer relationships $ 4,600 15 Tradenames 700 5 Technology 1,800 8 Other 190 5 Total $ 7,290

Inventories (Tables)

Inventories (Tables)	3 Months Ended
	Mar. 28, 2020
Inventory Disclosure [Abstract]
Inventories	Inventories include the cost of material, freight, direct labor and overhead utilized in the processing of our products and are stated at the lower of cost or net realizable value. Inventories were as follows: (in thousands) March 28, 2020 December 28, 2019 Bulk product $ 101,118 $ 114,308 Finished product 152,632 161,866 Packaging materials 4,621 4,639 Total $ 258,371 $ 280,813

Leases (Tables)

Leases (Tables)	3 Months Ended
	Mar. 28, 2020
Leases [Abstract]
Summary of Lease Expense	The following table summarizes the lease expense for the thirteen weeks ended March 28, 2020 and March 30, 2019 (in thousands) March 28, 2020 March 30, 2019 Operating lease expense $ 1,901 $ 1,928 Short-term lease expense 1,114 1,070 Total lease expense $ 3,015 $ 2,998
Summary of Supplemental Balance Sheet Information Related to Operating Leases	Supplemental balance sheet information related to our operating leases is as follows: (in thousands) March 28, 2020 Operating lease right-of-use assets $ 32,230 Other accrued liabilities $ 5,412 Long-term operating lease liabilities 29,714 Total operating lease liabilities $ 35,126 Weighted average remaining lease term (years) 9.16 Weighted average discount rate 5.18 %
Summary of Maturities of Operating Lease Liabilities	The following table summarizes the maturities of our lease liabilities for all operating leases as of March 28, 2020: (in thousands) March 28, 2020 2020 (Remainder of 2020) $ 4,357 2021 5,476 2022 5,004 2023 3,388 2024 3,451 2025 and thereafter 21,514 Total lease payments 43,190 Less: Imputed interest (8,064 ) Present value of lease liabilities $ 35,126

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	3 Months Ended
	Mar. 28, 2020
Goodwill And Intangible Assets Disclosure [Abstract]
Schedule of Goodwill	Goodwill Goodwill included the following: (in thousands) March 28, 2020 December 28, 2019 Balance at beginning of period $ 74,458 $ 72,606 Goodwill acquired 16,817 - Measurement period adjustments - 1,852 Balance at end of period $ 91,275 $ 74,458
Schedule of Intangible Assets	Intangible Assets Intangible assets included the following: March 28, 2020 December 28, 2019 (in thousands) Weighted Average Amortization Period Gross Carrying Value Accumulated Amortization Net Carrying Value Gross Carrying Value Accumulated Amortization Net Carrying Value Intangible assets subject to amortization Tradenames 11.2 $ 6,760 $ 1,128 $ 5,632 $ 6,060 $ 975 $ 5,085 Customer relationships 9.3 25,050 5,310 19,740 20,450 4,698 $ 15,752 Technology 8.3 2,167 135 2,032 367 74 $ 293 Other 4.1 430 86 344 240 65 $ 175 Total $ 34,407 $ 6,659 $ 27,748 $ 27,117 $ 5,812 $ 21,305

Revenue Recognition (Tables)

Revenue Recognition (Tables)	3 Months Ended
	Mar. 28, 2020
Revenue From Contract With Customer [Abstract]
Summary of Disaggregated Net Sales	The following tables present our disaggregated net sales by Type of Major Good / Product Line, and Geography. Thirteen Weeks Ended (in thousands) March 28, 2020 March 30, 2019 Powertrain $ 108,142 $ 95,163 Chassis 73,375 77,406 Automotive body 64,632 60,746 Hardware 11,581 10,476 Net sales $ 257,730 $ 243,791 Thirteen Weeks Ended (in thousands) March 28, 2020 March 30, 2019 Net sales to U.S. customers $ 241,392 $ 227,151 Net sales to non-U.S. customers $ 16,338 16,640 Net sales $ 257,730 $ 243,791

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	3 Months Ended
	Mar. 28, 2020
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Summary of Restricted Stock and RSU Award Activity	The following table summarizes our restricted stock and RSU award activity for the thirteen weeks ended March 28, 2020: Shares Weighted Average Price Balance at December 28, 2019 177,491 $ 76.70 Granted 72,369 $ 61.68 Vested (14,399 ) $ 65.13 Cancelled (22,488 ) $ 78.67 Balance at March 28, 2020 212,973 $ 72.17
Summary of Stock Option Activity	The following table summarizes our stock option activity for the thirteen weeks ended March 28, 2020: Shares Weighted Average Exercise Price Weighted Average Remaining Term (In years) Aggregate Intrinsic Value Balance at December 28, 2019 181,712 $ 70.78 Granted 98,974 $ 61.86 Exercised (419 ) $ 72.55 Balance at March 28, 2020 280,267 $ 67.63 5.1 $ 265,750 Options exercisable at March 28, 2020 96,386 $ 65.15 2.4 $ 265,750

Earnings Per Share (Tables)

Earnings Per Share (Tables)	3 Months Ended
	Mar. 28, 2020
Earnings Per Share [Abstract]
Schedule of Computation of Basic Earnings per Share and Diluted Earnings per Share	The following table sets forth the computation of basic earnings per share and diluted earnings per share: Thirteen Weeks Ended (in thousands, except per share data) March 28, 2020 March 30, 2019 Numerator Net income $ 22,775 $ 23,407 Denominator: Weighted average basic shares outstanding 32,354 32,801 Effect of stock-based compensation awards 72 88 Weighted average diluted shares outstanding 32,426 32,889 Earnings Per Share: Basic $ 0.70 $ 0.71 Diluted $ 0.70 $ 0.71

Basis of Presentation - Schedul

Basis of Presentation - Schedule of Revision of Prior Period Financial Statements - Consolidated Statement of Cash Flows (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 28, 2020	Mar. 30, 2019
Error Corrections And Prior Period Adjustments Restatement [Line Items]
Accounts receivable	$ (29,491)	$ 13,333
Accrued customer rebates and returns	4,471	(497)
Accrued compensation and other liabilities	6,808	3,043
Net cash provided by operating activities	$ 18,590	16,431
As Previously Reported [Member] | ASU 2014-09 [Member]
Error Corrections And Prior Period Adjustments Restatement [Line Items]
Accounts receivable		12,611
Accrued compensation and other liabilities		3,268
Net cash provided by operating activities		16,431
Adjustment [Member] | ASU 2014-09 [Member]
Error Corrections And Prior Period Adjustments Restatement [Line Items]
Accounts receivable		722
Accrued customer rebates and returns		(497)
Accrued compensation and other liabilities		$ (225)

Basis of Presentation - Sched_2

Basis of Presentation - Schedule of Revision of Prior Period Financial Statements - Consolidated Balance Sheet (Detail) - USD ($) $ in Thousands	Mar. 28, 2020	Dec. 28, 2019	Dec. 31, 2017
Assets
Accounts receivable, net	$ 423,301	$ 391,810	$ 241,880
Liabilities and shareholders’ equity
Accrued customer rebates and returns	$ 110,374	$ 105,903	6,522
ASU 2014-09 [Member]
Assets
Accounts receivable, net			337,417
Liabilities and shareholders’ equity
Accrued customer rebates and returns			102,059
ASU 2014-09 [Member] | Adjustment [Member]
Assets
Accounts receivable, net			95,537
Liabilities and shareholders’ equity
Accrued customer rebates and returns			$ 95,537

Business Acquisitions and Inv_3

Business Acquisitions and Investments - Additional Information (Detail) - USD ($) $ in Thousands	Jan. 02, 2020	Mar. 28, 2020	Dec. 28, 2019	Dec. 29, 2018
Business Acquisition [Line Items]
Business acquisition, goodwill		$ 91,275	$ 74,458	$ 72,606
Power Train Industries, Inc. [Member]
Business Acquisition [Line Items]
Fair value of previously held equity interest	$ 12,300
Equity method investment, ownership percentage	40.00%
Power Train Industries, Inc. [Member]
Business Acquisition [Line Items]
Business acquisition, percentage of outstanding stock acquired	60.00%
Total consideration paid for acquisition	$ 30,800
Business acquisition, value of outstanding stock acquired	18,000
Business acquisition, deferred payments	500
Business combination, separately recognized transactions, net gains and losses		$ 2,500
Business acquisition, goodwill	16,800
Business acquisition, identified intangibles	7,290
Business acquisition, other net assets	6,700
Business acquisition, cash	3,500
Business acquisition, accounts receivables	2,000
Business acquisition, inventory	5,600
Business acquisition, other assets and liabilities net	$ 4,400

Business Acquisitions and Inv_4

Business Acquisitions and Investments - Schedule of Valuation of Intangible Assets Acquired and Related Amortization Periods (Detail) - Power Train Industries, Inc. [Member] $ in Thousands	Jan. 02, 2020USD ($)
Business Acquisition [Line Items]
Valuation,Intangible assets	$ 7,290
Customer Relationships [Member]
Business Acquisition [Line Items]
Valuation,Intangible assets	$ 4,600
Amortization Period (in years)	15 years
Tradenames [Member]
Business Acquisition [Line Items]
Valuation,Intangible assets	$ 700
Amortization Period (in years)	5 years
Technology [Member]
Business Acquisition [Line Items]
Valuation,Intangible assets	$ 1,800
Amortization Period (in years)	8 years
Other [Member]
Business Acquisition [Line Items]
Valuation,Intangible assets	$ 190
Amortization Period (in years)	5 years

Sales of Accounts Receivable -

Sales of Accounts Receivable - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 28, 2020	Mar. 30, 2019	Dec. 28, 2019
Receivables [Abstract]
Sale of accounts receivable	$ 151.3	$ 172.8
Additional receivables outstanding if receivables had not been sold	375.7		$ 437.9
Factoring costs associated with the sales of accounts receivable	$ 2.8	$ 4.6
Maximum credit terms allow to customers	1 year

Inventories - Inventories (Deta

Inventories - Inventories (Detail) - USD ($) $ in Thousands	Mar. 28, 2020	Dec. 28, 2019
Inventory Disclosure [Abstract]
Bulk product	$ 101,118	$ 114,308
Finished product	152,632	161,866
Packaging materials	4,621	4,639
Total	$ 258,371	$ 280,813

Leases - Additional Information

Leases - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 28, 2020	Mar. 30, 2019
Lessee Lease Description [Line Items]
Financing leases	$ 0
Cash paid for operating leases	$ 1,900,000	$ 1,200,000
Minimum [Member]
Lessee Lease Description [Line Items]
Operating lease remaining lease term	1 year
Maximum [Member]
Lessee Lease Description [Line Items]
Operating lease remaining lease term	11 years

Leases - Summary of Lease Expen

Leases - Summary of Lease Expense (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 28, 2020	Mar. 30, 2019
Leases [Abstract]
Operating lease expense	$ 1,901	$ 1,928
Short-term lease expense	1,114	1,070
Total lease expense	$ 3,015	$ 2,998

Leases - Summary of Supplementa

Leases - Summary of Supplemental Balance Sheet Information Related to Operating Leases (Detail) - USD ($) $ in Thousands	Mar. 28, 2020	Dec. 28, 2019
Leases [Abstract]
Operating lease right-of-use assets	$ 32,230	$ 32,198
Other accrued liabilities	$ 5,412
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	us-gaap:OtherAccruedLiabilitiesCurrent
Long-term operating lease liabilities	$ 29,714	$ 29,730
Total operating lease liabilities	$ 35,126
Weighted average remaining lease term (years)	9 years 1 month 28 days
Weighted average discount rate	5.18%

Leases - Summary of Maturities

Leases - Summary of Maturities of Operating Lease Liabilities (Detail) $ in Thousands	Mar. 28, 2020USD ($)
Leases [Abstract]
2020 (Remainder of 2020)	$ 4,357
2021	5,476
2022	5,004
2023	3,388
2024	3,451
2025 and thereafter	21,514
Total lease payments	43,190
Less: Imputed interest	(8,064)
Present value of lease liabilities	$ 35,126

Goodwill and Intangible Asset_2

Goodwill and Intangible Assets - Schedule of Goodwill (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 28, 2020	Dec. 28, 2019
Goodwill And Intangible Assets Disclosure [Abstract]
Balance at beginning of period	$ 74,458	$ 72,606
Goodwill acquired	16,817
Measurement period adjustments		1,852
Balance at end of period	$ 91,275	$ 74,458

Goodwill and Intangible Asset_3

Goodwill and Intangible Assets - Schedule of Intangible Assets (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 28, 2020	Dec. 28, 2019
Finite Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 34,407	$ 27,117
Accumulated Amortization	6,659	5,812
Net Carrying Value	$ 27,748	21,305
Tradenames [Member]
Finite Lived Intangible Assets [Line Items]
Weighted Average Amortization Period	11 years 2 months 12 days
Gross Carrying Value	$ 6,760	6,060
Accumulated Amortization	1,128	975
Net Carrying Value	$ 5,632	5,085
Customer Relationships [Member]
Finite Lived Intangible Assets [Line Items]
Weighted Average Amortization Period	9 years 3 months 18 days
Gross Carrying Value	$ 25,050	20,450
Accumulated Amortization	5,310	4,698
Net Carrying Value	$ 19,740	15,752
Technology [Member]
Finite Lived Intangible Assets [Line Items]
Weighted Average Amortization Period	8 years 3 months 18 days
Gross Carrying Value	$ 2,167	367
Accumulated Amortization	135	74
Net Carrying Value	$ 2,032	293
Other [Member]
Finite Lived Intangible Assets [Line Items]
Weighted Average Amortization Period	4 years 1 month 6 days
Gross Carrying Value	$ 430	240
Accumulated Amortization	86	65
Net Carrying Value	$ 344	$ 175

Goodwill and Intangible Asset_4

Goodwill and Intangible Assets - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 28, 2020	Mar. 30, 2019
Goodwill And Intangible Assets Disclosure [Abstract]
Amortization expense	$ 0.8	$ 0.7

Debt - Additional Information (

Debt - Additional Information (Detail)	Mar. 23, 2020USD ($)	Mar. 28, 2020USD ($)LetterOfCredit	Dec. 30, 2017USD ($)	Jul. 31, 2006USD ($)
Debt Instrument [Line Items]
Amount drawn from credit facility		$ 99,000,000
Number of letters of credit outstanding | LetterOfCredit		2
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity			$ 100,000,000	$ 30,000,000
Expiration date of credit facility			2022-12
Line of credit facility, unused fee amount of threshold limit			$ 30,000,000
Line of credit facility unused fee percentage			0.10%
Interest rate of credit facility		1.64%
Credit facility default percentage		2.00%
Credit facility default amount		$ 0
Amount drawn from credit facility	$ 99,000,000
Borrowings under credit facility		99,000,000
Amount available under credit facility, net of letters of credit		200,000
Revolving Credit Facility [Member] | Maximum [Member]
Debt Instrument [Line Items]
Line of credit facility incremental borrowing capacity			$ 100,000,000
Line of credit facility additional borrowing capacity		100,000,000
Letters of Credit [Member]
Debt Instrument [Line Items]
Borrowings under credit facility		$ 800,000
LIBOR Market Index Rate [Member] | Revolving Credit Facility [Member] | Maximum [Member]
Debt Instrument [Line Items]
LIBOR basis points			1.25%
LIBOR Market Index Rate [Member] | Revolving Credit Facility [Member] | Minimum [Member]
Debt Instrument [Line Items]
LIBOR basis points			0.65%
LIBOR Rate [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
LIBOR basis points		0.65%
LIBOR Rate [Member] | Revolving Credit Facility [Member] | Maximum [Member]
Debt Instrument [Line Items]
LIBOR basis points			1.25%
LIBOR Rate [Member] | Revolving Credit Facility [Member] | Minimum [Member]
Debt Instrument [Line Items]
LIBOR basis points			0.65%

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 28, 2019	Mar. 28, 2020
Commitments And Contingencies [Line Items]
Estimated underpayment of duties amount	$ 2.8
Other Long-Term Liabilities [Member]
Commitments And Contingencies [Line Items]
Estimated liability of underpayment of duties		$ 2.8

Revenue Recognition - Additiona

Revenue Recognition - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 28, 2020	Dec. 28, 2019
Revenue From Contract With Customer [Abstract]
Maximum credit terms allow to customers	1 year
Revenue, performance obligation, description of payment terms	A receivable is recorded when our right to consideration is unconditional and only the passage of time is required before payment of that consideration is due.
Contract assets	$ 0	$ 0
Contract liabilities	$ 0	$ 0

Revenue Recognition - Summary o

Revenue Recognition - Summary of Disaggregated Net Sales (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 28, 2020	Mar. 30, 2019
Disaggregation Of Revenue [Line Items]
Net Sales	$ 257,730	$ 243,791
U.S. Customers [Member]
Disaggregation Of Revenue [Line Items]
Net Sales	241,392	227,151
Non-U.S. Customers [Member]
Disaggregation Of Revenue [Line Items]
Net Sales	16,338	16,640
Powertrain [Member]
Disaggregation Of Revenue [Line Items]
Net Sales	108,142	95,163
Chassis [Member]
Disaggregation Of Revenue [Line Items]
Net Sales	73,375	77,406
Automotive Body [Member]
Disaggregation Of Revenue [Line Items]
Net Sales	64,632	60,746
Hardware [Member]
Disaggregation Of Revenue [Line Items]
Net Sales	$ 11,581	$ 10,476

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 28, 2020	Mar. 30, 2019	May 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorized number of common stock shares for grant	1,200,000
Date of plan approval	May 16, 2018
Maximum grant period from date of plan approval	10 years
Shares available for grant under the plan	885,847
Compensation cost related to stock options	$ 200,000	$ 200,000
Stock options granted	98,974
Stock options exercised	419
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorized number of common stock shares for grant			1,000,000
Rate of discount on shares of common stock available for sale to eligible employees	15.00%
Number of shares purchased	0	0
Compensation cost	$ 100,000	$ 100,000
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cash generated from stock option exercises under the plan	100,000	100,000
Restricted Stock and Restricted Stock Units Award [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost related to restricted stock	1,000,000	700,000
Unrecognized compensation cost related to non-vested stock options	$ 10,300,000
Unrecognized compensation cost related to nonvested stock options, weighted-average period	2 years 9 months 18 days
Tax benefit generated from compensation cost and credited	$ 100,000	200,000
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to non-vested stock options	$ 4,000,000
Unrecognized compensation cost related to nonvested stock options, weighted-average period	3 years 3 months 18 days
Tax benefit generated from compensation cost and credited	$ 0	$ 0
Capitalized compensation cost	$ 0
Stock options granted	98,974	28,538
Stock options exercised	419	33,228

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Restricted Stock and RSU Award Activity (Detail)	3 Months Ended
	Mar. 28, 2020$ / sharesshares
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Beginning Balance, Shares | shares	177,491
Granted, Shares | shares	72,369
Vested, Shares | shares	(14,399)
Cancelled, Shares | shares	(22,488)
Ending Balance, Shares | shares	212,973
Beginning Balance, Weighted Average Price | $ / shares	$ 76.70
Granted, Weighted Average Price | $ / shares	61.68
Vested, Weighted Average Price | $ / shares	65.13
Cancelled, Weighted Average Price | $ / shares	78.67
Ending Balance, Weighted Average Price | $ / shares	$ 72.17

Stock-Based Compensation - Su_2

Stock-Based Compensation - Summary of Stock Option Activity (Detail)	3 Months Ended
	Mar. 28, 2020USD ($)$ / sharesshares
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Beginning Balance, Shares | shares	181,712
Granted, Shares | shares	98,974
Exercised, Shares | shares	(419)
Ending Balance, Shares | shares	280,267
Options Exercisable, Shares | shares	96,386
Beginning Balance, Weighted Average Exercise Price | $ / shares	$ 70.78
Granted, Weighted Average Exercise Price | $ / shares	61.86
Exercised, Weighted Average Exercise Price | $ / shares	72.55
Ending Balance, Weighted Average Exercise Price | $ / shares	67.63
Options Exercisable, Weighted Average Exercise Price | $ / shares	$ 65.15
Ending Balance, Weighted Average Remaining Terms (years)	5 years 1 month 6 days
Options Exercisable, Weighted Average Remaining Terms (years)	2 years 4 months 24 days
Ending Balance, Aggregate Intrinsic Value | $	$ 265,750
Options Exercisable, Aggregate Intrinsic Value | $	$ 265,750

Earnings Per Share - Additional

Earnings Per Share - Additional Information (Detail) - shares	3 Months Ended
	Mar. 28, 2020	Mar. 30, 2019
Earnings Per Share [Abstract]
Stock-based awards considered as anti-dilutive	91,273	114,000

Earnings Per Share - Schedule o

Earnings Per Share - Schedule of Computation of Basic Earnings per Share and Diluted Earnings per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 28, 2020	Mar. 30, 2019
Numerator
Net income	$ 22,775	$ 23,407
Denominator:
Weighted average basic shares outstanding	32,354	32,801
Effect of stock-based compensation awards	72	88
Weighted average diluted shares outstanding	32,426	32,889
Earnings Per Share:
Basic	$ 0.70	$ 0.71
Diluted	$ 0.70	$ 0.71

Common Stock Repurchases - Addi

Common Stock Repurchases - Additional Information (Detail) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 28, 2020	Dec. 28, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Repurchase and cancellation of shares	4,730	22,380
Common stock repurchased, value	$ 300,000	$ 1,900,000
Common stock repurchased, average price	$ 66.66	$ 87.26
Share repurchase program shares authorized to be repurchased expiration date	Dec. 31, 2020
Share Repurchase Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Repurchase and cancellation of shares	91,979	499,564
Common stock repurchased, value	$ 5,500,000	$ 39,400,000
Common stock repurchased, average price	$ 59.41	$ 78.84
Share repurchase program shares authorized to be repurchased	$ 400,000,000

Related Party Transactions - Ad

Related Party Transactions - Additional Information (Detail) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 28, 2020USD ($)Supplier	Dec. 26, 2020USD ($)	Dec. 28, 2019USD ($)
Related Party Transaction [Line Items]
Rental payments based upon the terms of the lease			$ 1,600
Right-of-use asset	$ 32,230		32,198
Lease liabilities	$ 35,126
Lease expiration date	Dec. 31, 2022
Canada [Member]
Related Party Transaction [Line Items]
Rental payments based upon the terms of the lease			$ 200
Lease expiration date	Apr. 30, 2019
Power Train Industries, Inc. [Member]
Related Party Transaction [Line Items]
Rental payments based upon the terms of the lease	$ 300
Steven L. Berman and Other Family Members [Member]
Related Party Transaction [Line Items]
Right-of-use asset	4,400
Lease liabilities	$ 4,400
Joint Venture [Member]
Related Party Transaction [Line Items]
Minority interests in number of suppliers | Supplier	2
Scenario, Forecast [Member]
Related Party Transaction [Line Items]
Rental payments based upon the terms of the lease		$ 1,600

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) $ in Millions	Mar. 28, 2020USD ($)
Income Tax Disclosure [Abstract]
Net unrecognized tax benefits	$ 2.3
Unrecognized tax benefits which would lower effective tax rate if recognized	2
Accrued interest and penalties related to uncertain tax positions	$ 0.4

Subsequent Events - Additional

Subsequent Events - Additional Information (Detail) - USD ($) $ in Millions	1 Months Ended	3 Months Ended
	Apr. 24, 2020	Mar. 28, 2020	Mar. 30, 2019
Subsequent Event [Line Items]
Factoring costs associated with the sales of accounts receivable		$ 2.8	$ 4.6
Subsequent Events [Member]
Subsequent Event [Line Items]
Receivables	$ 192
Factoring costs associated with the sales of accounts receivable	$ 3.7