Dorman Products (DORM) 10-K 26 Feb 20 2019 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 28, 2019	Feb. 21, 2020	Jun. 29, 2019
Cover [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 28, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
Trading Symbol	DORM
Title of 12(b) Security	Common Stock, $0.01 Par Value
Security Exchange Name	NASDAQ
Entity Registrant Name	DORMAN PRODUCTS, INC.
Entity Central Index Key	0000868780
Current Fiscal Year End Date	--12-28
Entity Well-known Seasoned Issuer	Yes
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
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		32,554,663
Entity Public Float			$ 1,964,315,544
Document Annual Report	true
Document Transition Report	false
Documents Incorporated by Reference	DOCUMENTS INCORPORATED BY REFERENCE Certain portions of the registrant's definitive proxy statement, in connection with its Annual Meeting of Shareholders, to be filed with the Securities and Exchange Commission within 120 days after December 28, 2019, are incorporated by reference into Part III of this Annual Report on Form 10-K.

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Income Statement [Abstract]
Net sales	$ 991,329	$ 973,705	$ 903,221
Cost of goods sold	651,504	600,424	544,572
Gross profit	339,825	373,281	358,649
Selling, general and administrative expenses	233,997	202,138	182,409
Income from operations	105,828	171,143	176,240
Other (expense) income, net	(21)	(8)	348
Income before income taxes	105,807	171,135	176,588
Provision for income taxes	22,045	37,533	69,989
Net income	$ 83,762	$ 133,602	$ 106,599
Earnings per share:
Basic	$ 2.57	$ 4.04	$ 3.14
Diluted	$ 2.56	$ 4.02	$ 3.13
Weighted average shares outstanding:
Basic	32,606	33,097	33,964
Diluted	32,688	33,207	34,052

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018
Current assets:
Cash and cash equivalents	$ 68,353	$ 43,458
Accounts receivable, less allowance for doubtful accounts of $957 and $982 in 2019 and 2018, respectively	391,810	400,663
Inventories	280,813	270,504
Prepaids and other current assets	13,614	5,652
Total current assets	754,590	720,277
Property, plant and equipment, net	101,837	98,647
Operating lease right-of-use assets	32,198
Goodwill	74,458	72,606
Intangible assets, net	21,305	25,164
Deferred tax asset, net	4,336	6,228
Other assets	52,348	55,184
Total	1,041,072	978,106
Current liabilities:
Accounts payable	90,437	109,096
Accrued compensation	9,782	14,515
Accrued customer rebates and returns	105,903	96,887
Other accrued liabilities	14,380	11,641
Total current liabilities	220,502	232,139
Long-term operating lease liabilities	29,730
Other long-term liabilities	13,297	13,550
Deferred tax liabilities, net	3,959	4,794
Commitments and contingencies (Note 11)
Shareholders' equity:
Common stock, par value $0.01; authorized 50,000,000 shares; issued and outstanding 32,558,168 and 33,004,861 shares in 2019 and 2018, respectively	326	330
Additional paid-in capital	52,605	47,861
Retained earnings	720,653	679,432
Total shareholders' equity	773,584	727,623
Total	$ 1,041,072	$ 978,106

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018
Statement Of Financial Position [Abstract]
Allowance for doubtful accounts and customer credits	$ 957	$ 982
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	50,000,000	50,000,000
Common stock, shares issued	32,558,168	33,004,861
Common stock, shares outstanding	32,558,168	33,004,861

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. 31, 2016	$ 601,642	$ 345	$ 44,187	$ 557,110
Beginning Balance, Shares at Dec. 31, 2016		34,517,633
Exercise of stock options	31		31
Exercise of stock options, shares		29,750
Compensation expense under Incentive Stock Plan	3,162		3,162
Purchase and cancellation of common stock	$ (76,129)	$ (10)	(1,848)	(74,271)
Purchase and cancellation of common stock, Shares	(19,110)	(1,025,475)
Issuance of non-vested stock, net of cancellations	$ 675	$ 1	674
Issuance of non-vested stock, net of cancellations, Shares		65,317
Other stock related activity, net of tax	(1,173)		(1,394)	221
Other stock related activity, net of tax, Shares		(15,701)
Net income	106,599			106,599
Ending Balance at Dec. 30, 2017	634,807	$ 336	44,812	589,659
Ending Balance, Shares at Dec. 30, 2017		33,571,524
Exercise of stock options	200		200
Exercise of stock options, shares		10,572
Compensation expense under Incentive Stock Plan	3,460		3,460
Purchase and cancellation of common stock	$ (45,351)	$ (7)	(1,167)	(44,177)
Purchase and cancellation of common stock, Shares	(26,280)	(648,503)
Issuance of non-vested stock, net of cancellations	$ 1,799	$ 1	1,798
Issuance of non-vested stock, net of cancellations, Shares		83,891
Other stock related activity, net of tax	(894)		(1,242)	348
Other stock related activity, net of tax, Shares		(12,623)
Net income	133,602			133,602
Ending Balance at Dec. 29, 2018	$ 727,623	$ 330	47,861	679,432
Ending Balance, Shares at Dec. 29, 2018	33,004,861	33,004,861
Exercise of stock options	$ 123		123
Exercise of stock options, shares		14,227
Compensation expense under Incentive Stock Plan	3,077		3,077
Purchase and cancellation of common stock	$ (41,339)	$ (5)	(939)	(40,395)
Purchase and cancellation of common stock, Shares	(22,380)	(521,944)
Issuance of non-vested stock, net of cancellations	$ 1,377	$ 1	1,376
Issuance of non-vested stock, net of cancellations, Shares		69,826
Other stock related activity, net of tax	(1,039)		1,107	(2,146)
Other stock related activity, net of tax, Shares		(10,707)
Net income	83,762			83,762
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

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	$ 83,762	$ 133,602	$ 106,599
Adjustments to reconcile net income to cash provided by operating activities:
Depreciation, amortization and accretion	25,915	28,391	22,224
Provision for doubtful accounts	39	(570)	299
Provision (benefit) from deferred income tax	1,058	(58)	4,676
Provision for non-cash stock compensation	3,077	3,460	3,162
Changes in assets and liabilities:
Accounts receivable	8,810	(61,413)	(5,709)
Inventories	(10,956)	(46,835)	(25,147)
Prepaids and other current assets	(7,659)	(853)	(3,748)
Other assets	1,672	(3,897)	(4,908)
Accounts payable	(19,079)	26,957	3,718
Accrued customer rebates and returns	9,016	(5,173)
Accrued compensation and other liabilities	(349)	4,501	(6,925)
Cash provided by operating activities	95,306	78,112	94,241
Cash Flows from Investing Activities:
Acquisitions, net of cash acquired		(28,040)	(59,987)
Property, plant and equipment additions	(29,560)	(26,106)	(24,450)
Purchase of investments		(5,000)	(10,000)
Cash used in investing activities	(29,560)	(59,146)	(94,437)
Cash Flows from Financing Activities:
Contingent consideration payments		(2,036)
Other stock related activity	365	249	(1,173)
Proceeds from exercise of stock options	123	201	31
Purchase and cancellation of common stock	(41,339)	(45,352)	(76,129)
Cash used in financing activities	(40,851)	(46,938)	(77,271)
Effect of exchange rate changes on Cash and Cash Equivalents		(261)	37
Net Increase (Decrease) in Cash and Cash Equivalents	24,895	(28,233)	(77,430)
Cash and Cash Equivalents, Beginning of Period	43,458	71,691	149,121
Cash and Cash Equivalents, End of Period	68,353	43,458	71,691
Supplemental Cash Flow Information
Cash paid for interest expense	338	250	291
Cash paid for income taxes	$ 28,923	$ 30,453	$ 74,647

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 28, 2019
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	1. Summary of Significant Accounting Policies Dorman Products, Inc. ("Dorman", the "Company", “we”, “us”, or “our”) is a supplier of replacement parts and fasteners for passenger cars, light trucks, and heavy duty trucks in the automotive aftermarket industry. We operate on a fifty-two, fifty-three week period ending on the last Saturday of the calendar year. The fiscal years ended December 28, 2019 (“fiscal 2019”), December 29, 2018 (“fiscal 2018”) and December 30, 2017 (“fiscal 2017”) were each fifty-two week periods. Principles of Consolidation . The Consolidated Financial Statements include our accounts and the accounts of our wholly-owned subsidiaries. All material intercompany accounts and transactions have been eliminated in consolidation. Use of Estimates in the Preparation of Financial Statements . The preparation of financial statements in accordance with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. Reclassifications . Certain prior year amounts have been reclassified to conform with the current-year presentation. Cash and Cash Equivalents . We consider all highly liquid short-term investments with original maturities of three months or less to be cash equivalents. 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 programs were accounted for as sales of accounts receivable and were removed from our Consolidated Balance Sheet at the time of the sales transactions. During fiscal 2019, fiscal 2018 and fiscal 2017, we sold $676.4 million, $604.7 million and $582.9 million, respectively, pursuant to these programs. If receivables had not been sold, $437.9 million and $378.5 million of additional receivables would have been outstanding at December 28, 2019 and December 29, 2018, respectively, based on standard payment terms. Selling, general and administrative expenses include $16.7 million, $14.5 million and $11.4 million in fiscal 2019, fiscal 2018 and fiscal 2017, respectively, of financing costs associated with these accounts receivable sales programs. Inventories . Inventories are stated at the lower of cost or net realizable value. Cost is determined by the first-in, first-out method. Inventories include the cost of material, freight, direct labor and overhead utilized in the processing of our products. We provide reserves for discontinued and excess inventory based upon historical demand, forecasted usage, estimated customer requirements and product line updates. Property, Plant and Equipment . Property, plant and equipment are recorded at cost and depreciated over their estimated useful lives, which range from three to thirty-nine years, using the straight-line method for financial statement reporting purposes and accelerated methods for income tax purposes. The costs of maintenance and repairs are expensed as incurred. Renewals and betterments are capitalized. Gains and losses on disposals are included in operating results. Estimated useful lives by major asset category are as follows: Buildings and building improvements 10 to 39 years Machinery, equipment and tooling 3 to 7 years Software and computer equipment 3 to 10 years Furniture, fixtures and leasehold improvements 3 to 7 years Long-Lived Assets Including Goodwill and Other Acquired Intangible Assets . Long-lived assets, including property, plant, and equipment and amortizable identifiable intangibles, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset or asset group may not be recoverable. The impairment review is a two-step process. First, recoverability is measured by comparing the carrying amount of an asset to the estimated undiscounted future cash flows expected to be generated by the asset. If the carrying amount exceeds the estimated undiscounted future cash flows, the second step of the impairment test is performed and an impairment charge is recognized in the amount by which the carrying amount of the asset exceeds its fair value. Assets to be disposed of would be separately presented in the balance sheet and reported at the lower of the carrying amount or fair value less costs to sell, and are no longer depreciated. The assets and liabilities of a disposal group classified as held for sale would be presented separately in the appropriate asset and liability sections of the balance sheet. Goodwill is reviewed for impairment on an annual basis or whenever events or changes in circumstances indicate the carrying value of the goodwill may be impaired. In regards to the annual test, we have 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. If we determine it is not more likely than not that the fair value of a reporting unit is less than its carrying amount, then performing the two-step impairment test is unnecessary. Purchase Accounting . The purchase price of an acquired business is allocated to the underlying tangible and intangible assets acquired and liabilities assumed based upon their respective fair market values, with the excess recorded as goodwill. Such fair market value assessments require judgments and estimates which may change over time and may cause the final amounts to differ materially from their original estimates. These adjustments to fair value assessments are recorded to goodwill over the purchase price allocation period which cannot exceed twelve months from the date of acquisition. Other Assets . Other assets include primarily long-term core inventory, deposits, and equity method investments. Certain products we sell contain parts that can be recycled, or as more commonly referred to in our industry, remanufactured. We refer to these parts as cores. A used core is remanufactured and sold to the customer as a replacement for a unit inside a vehicle. Customers and end-users that purchase remanufactured products will generally return the used core to us, which we then use in the remanufacturing process to make another finished good. Our core inventory consists of used cores purchased and held in our facilities, used cores that are in the process of being returned from our customers and end-users, and remanufactured cores held in finished goods inventory at our facilities. Our products that utilize a core primarily include instrument clusters, hybrid batteries, radios, and climate control modules. Long-term core inventory was $22.8 million and $28.1 million as of December 28, 2019 and December 29, 2018, respectively. Long-term core inventory is recorded at the lower of cost or net realizable value. Cost is determined based on actual purchases of core inventory. We believe that the most appropriate classification of core inventory is a long-term asset. According to guidance provided under the Financial Accounting Standards Board (“FASB”) Accounting Standards Codification(“ASC”), current assets are defined as “assets or resources commonly identified as those which are reasonably expected to be realized in cash or sold or consumed during the normal operating cycle of the business.” The determination of the long-term classification is based on our view that the value of the cores is not expected to be consumed or realized in cash during our normal annual operating cycle. We also have investments that we account for according to the equity method of accounting. The total book value of these investments was $ 19.3 million as of December 28, 2019 and $ 18.4 million as of December 29, 2018 , and these investments provided us $ 3.2 million and $ 2.2 million of income during fiscal 2019 and fiscal 2018 , respectively . Additionally, in fiscal 2018 we purchased an investment that we account for according to the cost method of accounting. The book value of this investment was $ 5.0 million as of December 28, 2019 . Other Accrued Liabilities. Other accrued liabilities include primarily accrued commissions, accrued income taxes, insurance liabilities, product warranties, and other current liabilities. We warrant our products against certain defects in material and workmanship when used as designed on the vehicle on which it was originally installed. We offer a limited lifetime warranty on most of our products. Our warranty limits the end-user’s remedy to the repair or replacement of the part that is defective. Product warranty reserves, which were $0.6 million as of December 28, 2019 and December 29, 2018, respectively, are based upon actual experience and forecasts using the best historical and current claim information available. Provisions and payments related to product warranty reserves were not material in fiscal 2019, fiscal 2018 or fiscal 2017. Revenue Recognition and Accrued Customer Rebates and Returns . 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 record estimates for cash discounts, product returns, promotional rebates, core return deposits, and other discounts in the period of the sale ("Customer Credits"). The provision for Customer Credits is recorded as a reduction from gross sales and reserves for Customer Credits are shown as an increase of accrued customer rebates and returns, which is included in current liabilities. Actual Customer Credits have not differed materially from estimated amounts. 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. As noted above, Customer Credits include core return deposits which are an estimate of the amount we believe we will refund to our customers when used cores are returned to us. The price we invoice to customers for remanufactured cores contain both the amount we charge to remanufacture the part and a deposit for the core. We charge a core deposit to encourage the customer to return the used core to us so that it can be used in our remanufacturing process. We allow our customers up to twenty-four months to return the used core to us. Core return deposits are reserved based on the expected deposits to be issued to customers based on historical returns. 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 FASB Accounting Standards Update (“ASU”) No. 2014-09, Revenue from Contracts with Customers, related to the balance sheet classification of accrued customer rebates and returns that are recognized in connection with sales of our products. We adopted this ASU on December 31, 2017, the beginning of our 2018 fiscal year. We previously recorded accrued customer rebates and returns that were expected to be issued as credits to our customers as a valuation account which offset accounts receivable. Accrued customer rebates and returns are now recorded as a current liability. Previously issued comparative financial statements, which were revised to correct the error noted above, are presented “As Revised” in the tables presented in the following footnotes. December 29, 2018 (in thousands) As Previously Reported Adjustment As Revised Revised Consolidated Balance Sheet Amounts: Assets Accounts receivable, net $ 310,114 $ 90,549 $ 400,663 Total current assets $ 629,728 $ 90,549 $ 720,277 Total assets $ 887,557 $ 90,549 $ 978,106 Liabilities and shareholders' equity Accrued customer rebates and returns $ 6,338 $ 90,549 $ 96,887 Total current liabilities $ 141,590 $ 90,549 $ 232,139 Total liabilities and shareholders' equity $ 887,557 $ 90,549 $ 978,106 Fiscal Year Ended December 29, 2018 (in thousands) As Previously Reported Adjustment As Revised Revised Consolidated Statement of Cash Flows from Operating Activities Amounts: Accounts receivable $ (66,403 ) $ 4,990 $ (61,413 ) Accrued customer rebates and returns $ — $ (5,173 ) $ (5,173 ) Accrued compensation and other liabilities $ 4,318 $ 183 $ 4,501 Net cash used in operating activities $ 78,112 $ — $ 78,112 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 Statement of Operations or our Consolidated Statements of Shareholders’ Equity in any period presented. Research and Development . Research and development costs are expensed as incurred. Research and development costs totaling $21.0 million in fiscal 2019, $20.1 million in fiscal 2018 and $20.0 million in fiscal 2017 have been recorded in selling, general and administrative expenses in the Consolidated Statements of Operations. Stock-Based Compensation . At December 28, 2019 and December 29, 2018, we had awards outstanding under two stock-based employee compensation plans, which are described more fully in Note 13, Capital Stock. We record compensation expense for all awards granted. The value of restricted stock issued is based on the fair value of our common stock on the grant date. For performance-based restricted stock awards tied to growth and adjusted pre-tax income, compensation costs related to the stock 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 as of the reporting date. The fair value of performance based restricted stock, for which the performance measure is total shareholder return, was determined using the Monte Carlo simulation model. The fair value of stock options granted was determined using the Black-Scholes option valuation model. Income Taxes . We follow the asset and liability method of accounting for deferred income taxes. Deferred tax assets and liabilities are determined based on the difference between the financial statement and tax bases of assets and liabilities. Deferred tax assets or liabilities at the end of each period are determined using the enacted tax rate expected to be in effect when taxes are actually paid or recovered. Unrecognized income tax benefits represent income tax positions taken on income tax returns that have not been recognized in the consolidated financial statements. The Company recognizes the benefit of an income tax position only if it is more likely than not (greater than 50%) that the tax position will be sustained upon tax examination, based solely on the technical merits of the tax position. Otherwise, no benefit is recognized. The tax benefits recognized are measured based on the largest benefit that has a greater than 50% likelihood of being realized upon ultimate settlement. Additionally, we accrue interest and related penalties, if applicable, on all tax exposures for which reserves have been established consistent with jurisdictional tax laws. Interest and penalties are classified as income tax expense in the Consolidated Statements of Operations. The Company does not anticipate material changes in the amount of unrecognized income tax benefits over the next year. Concentrations of Risk . Financial instruments that potentially subject us to concentrations of credit risk consist primarily of cash equivalents and accounts receivable. All cash equivalents are managed within established guidelines which limit the amount which may be invested with one issuer. A significant percentage of our accounts receivable have been, and will continue to be, concentrated among a relatively small number of automotive retailers and warehouse distributors in the United States. Our largest customer s accounted for 80% of net accounts receivable as of December 28, 2019 and 76% o f net accounts receivable as of December 29, 2018 , respectively . We continually monitor the credit terms and credit limits to these and other customers. In fiscal 2019 , approximately 79% of our products were purchased from suppliers located in a variety of foreign countries, with the largest portion coming from China. Fair Value Disclosures . The carrying value of financial instruments such as cash and cash equivalents, accounts receivable, accounts payable, and other current assets and liabilities approximate their fair value based on the short-term nature of these instruments. Additionally, the fair value of assets acquired and liabilities assumed are determined at the date of acquisition. We did not hold any foreign currency forward contracts at December 28, 2019 or December 29, 2018.

New and Recently Adopted Accoun

New and Recently Adopted Accounting Pronouncements	12 Months Ended
	Dec. 28, 2019
Accounting Changes And Error Corrections [Abstract]
New and Recently Adopted Accounting Pronouncements	2. New and Recently Adopted Accounting Pronouncements On December 30, 2018, the beginning of our 2019 fiscal year, we adopted ASU No. 2016-02, Leases, which replaces existing lease guidance. The ASU is intended to provide enhanced transparency and comparability by requiring lessees to record right-of-use assets and corresponding lease liabilities on the balance sheet. The new guidance will continue to classify leases as either finance or operating, with classification affecting the pattern of expense recognition in the statement of operations. Additionally, in August 2018, the FASB issued ASU 2018-11, Targeted Improvements to ASC 842, which includes an option to not restate comparative periods in transition and elect to use the effective date of ASC 842 as the date of initial application of transition. We adopted the standard using the modified retrospective approach and adoption resulted in right-of-use assets of $36.3 million and lease liabilities of $37.9 m In January 2017, the FASB issued ASU 2017-04, Simplifying the Test for Goodwill Impairment In June 2018, the FASB issued ASU 2018-07, Improvements to Nonemployee Share-Based Payment Accounting 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. This ASU removes certain exceptions for recognizing deferred taxes for investments, performing intraperiod allocation and calculating income taxes in 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 . H owever, at this time we do not believe this new guidance will have a material impact on our consolidated financial statements and related disclosures.

Business Acquisitions and Inves

Business Acquisitions and Investments	12 Months Ended
	Dec. 28, 2019
Business Combinations [Abstract]
Business Acquisitions and Investments	3. Business Acquisitions and Investments Flight Systems Automotive Group LLC On August 31, 2018, we acquired 100% of the outstanding stock of Flight Systems Automotive Group LLC (“Flight Systems” or “Flight”), a privately-held manufacturer and remanufacturer of complex automotive electronics and diesel fuel system components, based in Lewisberry, Pennsylvania. The purchase price was $27.5 million. We believe complex electronics components represent important growth opportunities for us and Flight’s product portfolio delivers valuable alternatives to aftermarket professionals. 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 $7.4 million in goodwill, $4.1 million of identified intangibles, and $16.0 million of other net assets, primarily $2.0 million of accounts receivables, $8.4 million of inventory, $4.4 million of fixed assets, and $1.2 million of net other assets and liabilities. During the year ended December 28, 2019, we recorded measurement and period adjustments of approximately $1.9 million to increase goodwill, $0.7 million to decrease inventory, and $1.2 million to decrease identified intangibles. These measurement period entries are included in the balances above. Our measurement period adjustments for Flight were complete as of December 28, 2019. The valuation of the intangible assets acquired and related amortization periods are as follows: (in thousands) Valuation Amortization Period (in years) Customer relationships $ 3,400 8 Tradenames 460 5 Other 240 5 Total $ 4,100 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 Flight and other factors. The goodwill is 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. MAS Automotive Distribution Inc. On October 26, 2017, we acquired 100% of the outstanding stock of MAS Automotive Distribution Inc. (“MAS Industries” or “MAS”), a privately-held manufacturer of premium chassis and control arms based in Montreal, Canada. The purchase price was $ 67.2 million net of $ 3.3 million of cash acquired and including contingent consideration and ot her purchase price adjustments. The Company believes MAS is complementary to our business and growth strategy. We see opportunities to leverage MAS’ existing presence in the automotive aftermarket, as well as our product development capabilities and financial resources to accelerate the growth of MAS’ premium chassis and control arms. We have included the results of MAS in our Consolidated Financial Statements since the acquisition date of October 26, 2017. The Consolidated Statement of Operations for the year ended December 29, 2018 includes $40.3 million of net sales and an immaterial amount of net income related to MAS. The Consolidated Balance Sheets presented reflect the acquisition of MAS Industries, effective October 26, 2017. The following table summarizes the preliminary fair value of the total consideration at October 26, 2017: (in thousands) Total Acquisition Date Fair Value Cash consideration (net of $3.3 million cash received) $ 56,859 Contingent cash consideration 7,982 Seller liability assumed 896 Working capital adjustment 1,486 Total consideration assigned to net assets acquired $ 67,223 Included in the table above is $8.0 million of estimated contingent payments which represented the acquisition date fair value of the estimated payments which will become due if certain sales thresholds are achieved through December 2020. The fair value of the contingent cash consideration was estimated by using an option pricing model framework, which represents our own assumptions and data, and is based on our best available information. As of December 28, 2019, we had $5.6 million recorded related to this payment. During fiscal 2019, the Company reduced this accrual by approximately $2.3 million from the December 29, 2018 ending accrual amount of $7.9 million. The decrease was primarily due to an update made to assumptions utilized in the determination of the fair value of the estimated expected payments, specifically forecasted net sales attributable to the earnout period, which resulted in a $2.6 million reduction in the ending accrual, which reduced Selling, General and Administrative expenses in fiscal 2019. This amount was offset by $0.3 million of accretion which was also included in Selling, General and Administrative expenses in fiscal 2019. The maximum contingent payment would be $11.7 million. Additionally, during fiscal 2018, we finalized working capital and other purchase price adjustments based on the MAS standalone audited 2017 financial statements, resulting in a payment to the former shareholder of $1.5 million. This amount had previously been accrued on our Consolidated Balance Sheet. 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. The following table summarizes the fair values of the assets acquired and liabilities assumed as of October 26, 2017 (in thousands): (in thousands) October 26, 2017 (As initially reported) Measurement period adjustments October 26, 2017 (As adjusted) Current assets (net of $3.3 million cash received) $ 21,756 $ 90 $ 21,846 Property, plant and equipment 1,615 - 1,615 Intangible assets 20,440 - 20,440 Goodwill 35,624 (193 ) 35,431 Total assets acquired 79,435 (103 ) 79,332 Current liabilities 5,691 (50 ) 5,641 Long-term liabilities 6,468 - 6,468 Total liabilities assumed 12,159 (50 ) 12,109 Net assets acquired $ 67,276 $ (53 ) $ 67,223 Our measurement period adjustments for MAS were complete as of September 29, 2018. The valuation of the intangible assets acquired and related amortization periods are as follows: (in thousands) Valuation Amortization Period (in years) Customer relationships $ 14,840 8-12 Tradenames 5,600 15 Total $ 20,440 The fair values of the Customer relationships and Tradenames were estimated using a discounted present value income approach. Under this method, an intangible asset’s fair value is equal to the present value of the incremental after-tax cash flows (excess earnings) attributable solely to the intangible asset over its remaining useful life. To calculate fair value, we used cash flows discounted at rates ranging from 15% to 17%, which were considered appropriate given the inherent risks associated with each type of asset. We believe that the level and timing of cash flows appropriately reflect market participant assumptions. The goodwill recognized is attributable primarily to strategic and synergistic opportunities related to existing automotive aftermarket businesses, the assembled workforce of MAS and other factors. The goodwill is expected to be deductible for tax purposes. On January 27, 2017 we acquired a 33% minority equity interest in a supplier for $10.0 million. We are accounting for our interest using the equity method of accounting, as our investment gives us the ability to exercise significant influence, but not control, over the supplier. On January 6, 2017, we acquired certain assets of Ingalls Engineering Company, Inc., a chassis and suspension business, primarily to expand our product portfolio. The purchase price was $4.8 million, comprised of $3.1 million of cash and $1.7 million of estimated contingent payments as of the date of acquisition. The contingent payment arrangement is based upon future net sales of the acquired business. In connection with this acquisition, we have completed our purchase price allocation procedures and recorded $2.8 million in goodwill and other intangible assets and $2.0 million of other net assets. All the intangible assets resulting from the asset purchase are expected to be deductible for tax purposes. The financial results of the acquisition have been included in the Consolidated Financial Statements since the acquisition date. During fiscal 2018, the Company reassessed the accrual for the contingent payments, resulting in a reduction of the accrual by $2.1 million, which reduced Selling, General and Administrative expenses in fiscal 2018, due to an update made to assumptions utilized in the determination of the fair value of the estimated expected payments, specifically forecasted net sales attributable to the earnout period. As of December 28, 2018, the Company did not have an accrual for these contingent payments.

Inventories

Inventories	12 Months Ended
	Dec. 28, 2019
Inventory Disclosure [Abstract]
Inventories	4. Inventories Inventories were as follows: (in thousands) December 28, 2019 December 29, 2018 Bulk product $ 114,308 $ 122,111 Finished product 161,866 144,897 Packaging materials 4,639 3,496 Total $ 280,813 $ 270,504

Property, Plant and Equipment

Property, Plant and Equipment	12 Months Ended
	Dec. 28, 2019
Property Plant And Equipment [Abstract]
Property, Plant and Equipment	5. Property, Plant and Equipment Property, plant and equipment include the following: (in thousands) December 28, 2019 December 29, 2018 Buildings $ 37,513 $ 34,943 Machinery, equipment and tooling 126,663 115,656 Furniture, fixtures and leasehold improvements 5,308 6,199 Software and computer equipment 80,397 79,349 Total 249,881 236,147 Less-accumulated depreciation and amortization (148,044 ) (137,500 ) Property, plant and equipment, net $ 101,837 $ 98,647 Depreciation and amortization expenses associated with property, plant, and equipment were $25.4 million, $25.4 million, and $21.5 million in fiscal 2019, fiscal 2018, and fiscal 2017, respectively.

Leases

Leases	12 Months Ended
	Dec. 28, 2019
Leases [Abstract]
Leases	6. Leases As discussed in Note 2, we adopted ASU No. 2016-02, Leases, on December 30, 2018, the beginning of our fiscal 2019, using the modified retrospective approach. We determine whether an arrangement is a lease at inception. This determination generally depends on whether the arrangement conveys the right to control the use of an identified fixed asset explicitly or implicitly for a period of time in exchange for consideration. Control of an underlying asset is conveyed if we obtain the rights to direct the use of and to obtain substantially all of the economic benefit from the use of the underlying asset. We have operating leases for distribution centers, sales offices and certain warehouse and office equipment. Our operating leases have remaining lease terms of 1 to 12 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. Substantially all of our equipment leases and some of our real estate leases have terms of less than one year. Some of our operating lease agreements include variable lease costs, primarily taxes, insurance, common area maintenance or increases in rental costs related to inflation. 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. The incremental borrowing rate is not a commonly quoted rate and is derived through a combination of inputs including our credit rating and the impact of full collateralization. The incremental borrowing rate is based on our collateralized borrowing capabilities over a similar term of the lease payments. We utilized the consolidated group borrowing rate for all leases as we operate a centralized treasury operation. Operating lease payments are recognized on a straight-line basis over the lease term. We had no finance leases as of December 28, 2019. Practical Expedients and Accounting Policy Elections In accordance with the guidance on leases and as permitted by the FASB, we have elected to use certain practical expedients and policy elections. - We have elected to include both lease and non-lease components as a single lease component, as non-lease components of contracts have not historically been material. - We have elected to account for leases with terms of one year or less as short-term leases and, as such, lease with terms of less than one year are not included in the right-of-use assets or lease liabilities. As of December 28, 2019, there was no material variable lease costs or sublease income. Cash paid for operating leases was $6.0 million during the year ended December 28, 2019, which is classified in operating activities on the Consolidated Statements of Cash Flows . The following table summarizes the lease expense for the year ended December 28, 2019 : (in thousands) December 28, 2019 Operating lease expense $ 7,362 Short-term lease expense 4,547 Total lease expense $ 11,909 Supplemental balance sheet information related to our operating leases is as follows: (in thousands) December 28, 2019 Operating lease right-of-use assets $ 32,198 Other accrued liabilities $ 5,348 Long-term operating lease liabilities 29,730 Total operating lease liabilities $ 35,078 Weighted average remaining lease term (years) 10.83 Weighted average discount rate 6.32 % The following table summarizes the maturities of our lease liabilities for all operating leases as of December 28, 2019: (in thousands) December 28, 2019 2020 $ 6,935 2021 4,977 2022 4,904 2023 3,388 2024 3,452 2025 and thereafter 21,514 Total lease payments 45,170 Less: Imputed interest (10,092 ) Present value of lease liabilities $ 35,078 For the year ended December 29, 2018, minimum rental payments under operating leases were recognized on a straight-line basis over the term of the lease including any periods of free rent. Rent expense for operating leases, including payments for short-term equipment and storage rentals, was $6.9 million in fiscal 2018 and $5.7 million in fiscal 2017. Minimum future rental payments required under operating leases in effect as of December 29, 2018 were as follows: (in thousands) December 29, 2018 2019 $ 5,489 2020 5,416 2021 4,972 2022 4,599 2023 3,013 2024 and thereafter 24,297 Total rental payments $ 47,786

Goodwill and Intangible Assets

Goodwill and Intangible Assets	12 Months Ended
	Dec. 28, 2019
Goodwill And Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	7. Goodwill and Intangible Assets Goodwill Goodwill included the following: (in thousands) December 28, 2019 December 29, 2018 Balance at beginning of period $ 72,606 $ 65,999 Goodwill acquired - 6,800 Measurement period adjustment 1,852 (193 ) Balance at end of period $ 74,458 $ 72,606 Intangible Assets Intangible assets, subject to amortization, included the following: December 28, 2019 December 29, 2018 (dollars in thousands) Weighted Average Amortization Period (years) Gross Carrying Value Accumulated Amortization Net Carrying Value Gross Carrying Value Accumulated Amortization Net Carrying Value Intangible assets subject to amortization Tradenames 12.3 $ 6,060 $ 975 $ 5,085 $ 7,590 $ 516 $ 7,074 Customer relationships 8.0 20,450 4,698 15,752 20,130 2,582 17,548 Technology 12.0 367 74 293 367 49 318 Other 3.7 240 65 175 240 16 224 Total $ 27,117 $ 5,812 $ 21,305 $ 28,327 $ 3,163 $ 25,164 Amortization expense was $2.6 million in fiscal 2019, $2.3 million in fiscal 2018 and $0.5 million in fiscal 2017. The estimated future amortization expense for intangible assets is summarized as follows: (in thousands) 2020 $ 2,674 2021 2,674 2022 2,674 2023 2,626 2024 2,530 Thereafter 8,127 Total $ 21,305

Long-Term Debt

Long-Term Debt	12 Months Ended
	Dec. 28, 2019
Debt Disclosure [Abstract]
Long-Term Debt	8. Long-Term 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. 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 December 28, 2019 , we were no t 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 an unused fee of 0.10 % on the average daily unused portion of the facility , provided the unused fee will not be charged on the first $ 30 million of the revolving credit facility . As of December 28, 2019 , we were not in default in respect to the credit agreement . As of December 28, 2019 , there were no borrowings under the credit agreement and we had 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 letters of credit, we had approximately $ 99.2 million available under the credit agreement at December 28, 2019 .

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 28, 2019
Related Party Transactions [Abstract]
Related Party Transactions	9. Related Party Transactions We have a non-cancelable operating lease for our primary operating facility from a partnership in which Steven L. Berman, our Executive Chairman, and his family members are partners. Total rental payments each year to the partnership under the lease arrangement were $1.6 million in each of fiscal 2019, fiscal 2018 and fiscal 2017. This lease was renewed during November 2016, effective as of January 1, 2018, and will expire on December 31, 2022. In the opinion of our Audit Committee, the terms and rates of this lease were no less favorable than those which could have been obtained from an unaffiliated party when the lease was renewed during November 2016. We are a partner in a joint venture with one of our suppliers and we own a minority interest in two other suppliers. Purchases from these companies, since we acquired our investment interests were $23.2 million in fiscal 2019 and $20.3 million in fiscal 2018 and $16.5 million in fiscal 2017.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 28, 2019
Income Tax Disclosure [Abstract]
Income Taxes	10. Income Taxes U.S. Tax Reform: Tax Cuts and Jobs Act On December 22, 2017, the Tax Cuts and Jobs Act (the "TCJA") was enacted in the United States. The TCJA represented sweeping changes in U.S. tax law. Among the numerous changes in tax law, the TCJA permanently reduced the U.S. corporate income tax rate to 21% beginning in 2018; allowed 100% expensing for qualified property placed in service after September 27, 2017; imposed a one-time transition tax on deferred foreign earnings; established a participation exemption system by allowing a 100% dividends received deduction on qualifying dividends paid by foreign subsidiaries; limited deductions for net interest expense; and expanded the U.S. taxation of foreign earned income to include "global intangible low taxed income." The TCJA transitions the U.S. from a worldwide tax system to a territorial tax system. Under previous law, companies could indefinitely defer U.S. income taxation on unremitted foreign earnings. The TCJA imposed a one-time transition tax on deferred foreign earnings of 15.5% for liquid assets and 8% for illiquid assets, payable in defined increments over eight years. We did not recognize any transition tax expense due to having no accumulated earnings and profits in our non-U.S. subsidiaries. The components of the income tax provision (benefit) are as follows: (in thousands) 2019 2018 2017 Current: Federal $ 19,090 $ 33,362 $ 56,641 State 2,091 2,618 8,293 Foreign (194 ) 1,611 379 20,987 37,591 65,313 Deferred: Federal 2,084 1,398 4,582 State (280 ) 186 343 Foreign (746 ) (1,642 ) (249 ) 1,058 (58 ) 4,676 Total $ 22,045 $ 37,533 $ 69,989 The following is a reconciliation of income taxes at the statutory tax rate to the Company's effective tax rate: 2019 2018 2017 Federal taxes at statutory rate 21.0 % 21.0 % 35.0 % State taxes, net of federal tax benefit 1.3 1.3 3.4 Research and development tax credit (0.5 ) (0.4 ) (0.3 ) Federal permanent items (0.3 ) (0.1 ) (0.4 ) Tax reform — — 2.5 Effect of foreign operations (1.1 ) (0.2 ) (0.1 ) Other 0.4 0.3 (0.5 ) Effective tax rate 20.8 % 21.9 % 39.6 % At December 28, 2019, we had $2.3 million of unrecognized tax benefits, $2.0 million of which would affect our effective tax rate if recognized. The following table summarizes the change in unrecognized tax benefits for the three years ended December 28, 2019: (in thousands) 2019 2018 2017 Balance at beginning of year $ 2,390 $ 2,301 $ 3,567 Reductions due to lapses in statutes of limitations (200 ) (95 ) (181 ) Reductions due to tax positions settled — (368 ) (4,543 ) Reductions due to reversals of prior year positions (28 ) (4 ) — Additions based on tax positions taken during the prior period — — 3,005 Additions based on tax positions taken during the current period 139 556 453 Balance at end of year $ 2,301 $ 2,390 $ 2,301 We recognize interest and penalties related to unrecognized tax benefits in income tax expense. As of December 28, 2019, we had approximately $0.3 million of accrued interest and penalties related to unrecognized tax benefits. Deferred income taxes result from timing differences in the recognition of revenue and expense for tax and financial statement purposes. The sources of temporary differences are as follows: (in thousands) December 28, 2019 December 29, 2018 Assets: Inventories $ 9,545 $ 9,006 Accounts receivable 10,695 11,052 Operating lease liability 7,273 - Accrued expenses 1,974 1,792 Foreign tax credits 844 1,050 Total deferred tax assets 30,331 22,900 Valuation allowance (844 ) (1,050 ) Net deferred tax assets 29,487 21,850 Liabilities: Depreciation 10,296 9,094 Goodwill and intangible assets 11,742 11,310 Operating lease right of use asset 6,656 - Other 416 12 Gross deferred tax liabilities 29,110 20,416 Net deferred tax assets $ 377 $ 1,434 Based on our history of taxable income and our projection of future earnings, we believe that it is more likely than not that sufficient taxable income will be generated in the foreseeable future to realize the remaining net deferred tax assets. We file income tax returns in the United States, India, China, Canada and Mexico. All years before 2016 are closed for 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 China and Canada. All tax years remain open for Mexico and India.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 28, 2019
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	11. Commitments and Contingencies Shareholders’ Agreement . A shareholders’ agreement was entered into in September 1990 and amended and restated on July 1, 2006. Under the agreement, each of the late Richard Berman, Steven Berman, Jordan Berman, Marc Berman, Fred Berman, Deanna Berman and additional shareholders named in the agreement has, among other things, granted the others of them rights of first refusal, exercisable on a pro rata basis or in such other proportions as the exercising shareholders may agree, to purchase shares of our common stock which any of them, or upon their deaths their respective estates, proposes to sell to third parties. We have agreed with these shareholders that, upon their deaths, to the extent that any of their shares are not purchased by any of these surviving shareholders and may not be sold without registration under the Securities Act of 1933, as amended (the "1933 Act"), we will use our best efforts to cause those shares to be registered under the 1933 Act. The expenses of any such registration will be borne by the estate of the deceased shareholder. The additional shareholders that are a party to the agreement are trusts affiliated with the late Richard Berman, Steven Berman, Jordan Berman, Marc Berman or Fred Berman, or each person’s respective spouse or children. CBP Matter. During 2019, we voluntarily commenced an internal review into our product import classifications after discovering that we previously misclassified certain products that we imported into the United States. We also informed United States Customs & Border Protection (“CBP”) that we were commencing a voluntary disclosure process with CBP where, after completing our internal review, we would voluntarily disclose to CBP any identified product misclassifications and reimburse CBP for any resulting underpayment of duties. Since discovering the misclassifications, we have taken corrective actions with respect to the ongoing classification of our products and payment of duties on products being imported into the United States. Through our internal review, we identified misclassifications resulting in both underpayments and overpayments of duties to CBP. As of the date of this filing, our internal review is substantially complete. Since we are voluntarily reporting to CBP through a prior disclosure process, we believe our liability to CBP in that prior disclosure process will be limited to the unpaid duties, after deducting the overpayment of duties, and interest on such net unpaid duties for the last five years, which is the applicabl e statute of limitations. The Company recorded an estimated net charge of $ 2.8 million in its Statement of Operations for the year ended December 28, 2019, which represents the Company’s estimated underpayments of duties to CBP due to misclassifications after deducting estimated overpayments of duties to CBP due to misclassifications, plus applicable interest. The estimated net charge is reported between Cost of Goods Sold of $ 2.4 million and Selling, General and Administrative expenses representing estimated interest on the amounts owed to CBP of $ 0.4 million. The charge 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

Revenue Recognition

Revenue Recognition	12 Months Ended
	Dec. 28, 2019
Revenue From Contract With Customer [Abstract]
Revenue Recognition	12. Revenue Recognition The FASB issued ASU No. 2014-09, Revenue from Contracts with Customers outli As part of our impact assessment of the implementation of the new revenue recognition guidance, we reviewed our historical accounting policies and practices to identify potential differences with the requirements of the new revenue recognition standard, as it related to our contracts and sales arrangements, as well as technical considerations for our future transaction accounting, financial reporting, and disclosure requirements. We adopted the guidance in the first quarter of 2018, as required, electing to use a modified retrospective adoption approach. Comparative information has not been restated and continues to be reported under the accounting standards in effect for those periods. In addition, we elected to apply certain of the permitted practical expedients within the revenue recognition guidance and make certain accounting policy elections including those related to significant financing components, sales taxes and shipping and handling activities. Adoption of the revenue recognition standard did not have a material impact on our reported earnings, cash flows, or balance sheet, however, adoption did increase the amount and level of disclosures concerning our net sales. Business Description We are a supplier of replacement parts and fasteners for passenger cars, light trucks, and heavy duty trucks in the automotive aftermarket. We group our products into four major classes: power-train, automotive body, chassis, and hardware. Our products are sold primarily in the United States through automotive aftermarket retailers, national and regional local warehouse distributors and specialty markets, and salvage yards. We also distribute automotive replacement parts internationally, with sales primarily into Canada, Mexico, Europe, the Middle East, and Australia. We warrant our products against certain defects in material and workmanship when used as designed on the vehicle on which it was originally installed. We offer a limited lifetime warranty on most of our products. Our warranty limits the customer’s remedy to the repair or replacement of the part that is defective. Our primary source of revenue is from contracts with and p urchase 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 col lection 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 wh ich we would be entitled. The most likely amount method considers the single most likely amount from a range of p ossible consideration amounts. This method is utilized for all of our variabl e consideration. We record estimates for cash discounts, product returns, promotional rebates, core return deposits and other discounts in the period the related product revenue is recognized (“Customer Credits”). The provision for Customer Credits is recorded as a reduction from gross sales and reserves for Customer Credits are shown as an increase of accrued customer rebates and returns. Actual Customer Credits 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 in the new standard. All of our revenue was recognized under the point of time approach in accordance with the revenue standard during fiscal 2019 and fiscal 2018. 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. A summary of our application of the five-step model is as follows: (i) In most instances, our contract with a customer is the customer’s purchase order. Upon acceptance of the purchase order, a contract exists with a customer as a sales agreement indicates approval and commitment of the parties, identifies the rights of both parties, identifies the payment terms, has commercial substance, and it is probable that we will collect the consideration to which we will be entitled in exchange for the goods transferred to the customer. For certain customers, we may also enter into a sales agreement which outlines pricing considerations as well as the framework of terms and conditions which apply to future purchase orders for that customer. In these situations, our contract with the customer is both the sales agreement as well as the specific customer purchase order. As our contract with a customer is typically for a single transaction or customer purchase order, the duration of the contract is typically one year or less. As a result, we have elected to apply certain practical expedients and omit certain disclosures of remaining performance obligations for contracts which have an initial term of one year or less as permitted by the FASB. (ii) We identify a performance obligation in a contract for each distinct good or service promised that are separately identifiable from other promises in the contract. (iii) We identify the transaction price as the amount of consideration including variable consideration that we expect to be entitled in exchange for transferring control of goods and/or services to our customers. (iv) We allocate the transaction price to each performance obligation on the basis of the amount of consideration to which we expect to be entitled in exchange for satisfying each performance obligation. (v) We recognize revenue when we satisfy a performance obligation by transferring control of the promised goods. Practical Expedients and Accounting Policy Elections In accordance with the guidance on revenue recognition and as permitted by the FASB, we have elected to use certain practical expedients and policy elections. - We have elected to not adjust the promised amount of consideration for the effects of a significant financing component as we expect, at contract inception, that the period between when we transfer a promised good or service to the customer and when the customer pays for that good or service will be one year or less. - We have elected to expense costs to obtain a contract as incurred when the expected period of benefit, and therefore the amortization period, is one year or less. - We have elected to exclude from the measurement of the transaction price all taxes assessed by a governmental authority that are both imposed on and concurrent with a specific revenue-producing transaction and collected by the entity for a customer, including sales, use, value-added, excise and various other taxes. - We have elected to account for shipping and handling activities that occur after the customer has obtained control of a good as a fulfilment activity rather than a separate 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 good 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 December 28, 2019 or December 29, 2018. 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 December 28, 2019 or December 29, 2018. Disaggregated Revenue The following tables present our disaggregated net sales by Type of Major Good / Product Line, and Geography. (in thousands) 2019 2018 2017 Powertrain $ 395,975 $ 393,979 $ 374,372 Chassis 297,350 278,584 238,239 Automotive Body 251,506 256,344 245,869 Hardware 46,498 44,798 44,741 Net Sales $ 991,329 $ 973,705 $ 903,221 (in thousands) 2019 2018 2017 Net Sales to U.S. Customers $ 929,908 $ 913,181 $ 847,394 Net Sales to Non-U.S. Customers 61,421 60,524 55,827 Net Sales $ 991,329 $ 973,705 $ 903,221

Capital Stock

Capital Stock	12 Months Ended
	Dec. 28, 2019
Equity [Abstract]
Capital Stock	13. Capital Stock Controlling Interest by Officers, Directors and Family Members . As of December 28, 2019, Steven Berman, the Executive Chairman of the Company, and members of his family beneficially own approximately 18% of the outstanding shares of our common stock and can influence matters requiring approval of shareholders, including the election of the Board of Directors and the approval of significant transactions. Undesignated Stock . We have 50,000,000 shares authorized of undesignated capital stock for future issuance. The designation, rights and preferences of such shares will be determined by our Board of Directors. Incentive Stock Plan . Prior to May 16, 2018, we issued stock compensation grants under our 2008 Stock Option and Stock Incentive Plan. On May 16, 2018, our shareholders approved our 2018 Stock Option and Stock Incentive Plan (the “2018 Plan” or the “Plan”), which supersedes our 2008 Stock Option and Stock Incentive Plan. All future stock compensation grants will be issued under the 2018 Plan. Under the terms of the 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 and stock options or combinations thereof to officers, directors, employees, consultants and advisors. Grants under the 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 approved by the Board of Directors, 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 approved by our Board of Directors. At December 28, 2019, 1,034,023 shares were available for grant under the Plan. Restricted Stock We grant restricted stock to certain employees and members of our Board of Directors. We retain the restricted stock, and any dividends paid thereon, until the vesting restrictions have been met. For time-based restricted stock 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 awards tied to growth and adjusted pre-tax income, compensation costs related to the stock 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 as of the reporting date. In 2019, we introduced performance-based shares that vest based on our total shareholder return ranking relative to the S&P midcap 400 growth index over a three-year performance period. For performance-based restricted stock awards tied to total shareholder return, compensation cost related to the stock 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. This valuation technique includes estimating the movement of stock prices and the effects of volatility, interest rates and dividends. The following table summarizes the weighted average valuation assumptions used to calculate the fair value of total shareholder return performance restricted stock granted: 2019 Share price $ 82.03 Expected dividend yield 0.0 % Expected stock price volatility 27.7 % Risk-free interest rate 2.5 % Expected life 2.8 years The share price is the company’s closing share price as of the valuation date. The risk-free rate is based on the U.S. Treasury security with terms equal to the expected time of exercise as of the grant date. The weighted-average grant-date fair value of total shareholder return based performance restricted stock granted during fiscal 2019 was $ 81.44 . Compensation cost related to restricted stock was $2.1 million, $2.6 million and $2.8 million in fiscal 2019, fiscal 2018 and fiscal 2017, respectively. The compensation costs were classified as selling, general and administrative expense in the Consolidated Statements of Operations. No cost was capitalized during fiscal 2019, fiscal 2018 or fiscal 2017. The following table summarizes our restricted stock activity for the three years ended December 28, 2019: Shares Weighted Average Price Balance at December 31, 2016 145,363 $ 49.22 Granted 70,611 $ 78.27 Vested (56,953 ) $ 56.03 Cancelled (5,294 ) $ 51.56 Balance at December 30, 2017 153,727 $ 59.94 Granted 89,798 $ 73.51 Vested (45,707 ) $ 62.56 Cancelled (27,081 ) $ 75.39 Balance at December 29, 2018 170,737 $ 63.94 Granted 92,396 $ 81.92 Vested (41,586 ) $ 55.72 Cancelled (44,056 ) $ 58.03 Balance at December 28, 2019 177,491 $ 76.70 As of December 28, 2019, there was approximately $6.3 million of unrecognized compensation cost related to nonvested restricted stock, which is expected to be recognized over a weighted-average period of approximately 2.6 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. T he excess tax benefit generated from restricted shares which vested was $0.2 million in fiscal 2019, $0.1 million in fiscal 2018 and $0.4 million in fiscal 2017 and was credited to income tax expense. Stock Options We grant stock options to certain employees. We expense the grant-date fair value of stock options. Compensation cost is recognized over the vesting or performance period. Compensation cost charged against income was $0.7 million in fiscal 2019, $0.5 million in fiscal 2018 and $0.3 million in fiscal 2017, respectively We used the Black-Scholes option valuation model to estimate the fair value of stock options granted in fiscal 2019, fiscal 2018 and fiscal 2017. 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 is based on the U.S. Treasury security with terms equal to the expected time of exercise as of the grant date. The weighted-average grant-date fair value of options granted during fiscal 2019 was $24.32, fiscal 2018 was $15.88 and fiscal 2017 was $15.81 per option. The following table summarizes the weighted average valuation assumptions used to calculate the fair value of options granted: 2019 2018 2017 Expected dividend yield 0 % 0 % 0 % Expected stock price volatility 28 % 27 % 27 % Risk-free interest rate 2.3 % 2.6 % 1.5 % Expected life of options 5.4 years 3.0 years 3.0 years The following table summarizes our stock option activity for the three years ended December 28, 2019: Shares Option Price per Share Weighted Average Price Weighted Average Remaining Terms (years) Aggregate Intrinsic Value Balance at December 31, 2016 101,084 $5.67 – $53.32 $ 29.52 Granted 58,024 $69.02 – $82.59 $ 78.58 Exercised (32,751 ) $6.90 – $41.59 $ 7.69 Cancelled (3,810 ) $41.59 – $78.64 $ 56.72 Balance at December 30, 2017 122,547 $5.67 – $82.59 $ 57.74 Granted 81,995 $68.93 – $82.94 $ 73.84 Exercised (15,113 ) $5.67 – $78.64 $ 39.38 Cancelled (960 ) $ 72.55 $ 72.55 Balance at December 29, 2018 188,469 $7.74 – $82.94 $ 66.14 Granted 44,025 $73.72 – $84.93 $ 81.84 Exercised (38,009 ) $7.74 – $78.76 $ 58.96 Cancelled (12,773 ) $41.59 – $82.94 $ 75.52 Balance at December 28, 2019 181,712 $41.59 – $84.93 $ 70.78 3.8 $ 1,308,808 Options exercisable at December 28, 2019 63,432 $41.59 – $82.94 $ 62.39 2.3 $ 897,145 As of December 28, 2019, there was approximately $1.6 million of unrecognized compensation cost related to nonvested stock options, which is expected to be recognized over a weighted-average period of approximately 2.7 years. The following table summarizes information concerning currently outstanding and exercisable options at December 28, 2019: Options Outstanding Options Exercisable Range of Exercise Price Number Outstanding Weighted Average Remaining Contractual Life (years) Weighted Average Exercise Price Number Exercisable Weighted Average Exercise Price $41.59 - $61.13 38,848 1.3 $ 45.94 29,136 $ 45.94 $61.14 - $73.13 52,413 3.9 $ 71.89 13,762 $ 71.68 $73.14 - $78.70 24,654 3.4 $ 77.60 9,650 $ 78.64 $78.71 - $82.31 35,803 5.2 $ 80.65 6,871 $ 78.76 $82.32 - $84.93 29,994 5.6 $ 83.66 4,013 $ 82.83 Balance at December 28, 2019 181,712 3.8 $ 70.78 63,432 $ 62.39 Cash received from option exercises was $0.1 million in fiscal 2019, $0.2 million in fiscal 2018, and less than $0.1 million in fiscal 2017. There was no excess tax benefit generated from option exercises in fiscal 2019 or fiscal 2018. The excess tax benefit generated from option exercises was $0.6 million in fiscal 2017 and was credited to income tax expense. Performance-Based Long Term Award Program. The Compensation Committee of our Board of Directors previously approved a performance-based long term award program (the “Program”) that connects compensation for certain of our executives to the three-year Employee Stock Purchase Plan. In May 2017, our shareholders’ approved the Dorman Products, Inc. Employee Stock Purchase Plan (the “ESPP”), which makes available 1,000,000 shares of our common stock for sale to eligible employees. The purpose of this plan, 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. Share purchases under the plan are made twice annually, beginning in March 2018. There were 21,200 and 21,173 shares purchased under this plan during fiscal 2019 and 2018, respectively. There were no shares purchased under this plan during fiscal 2017. Compensation cost under the ESPP plan was $0.3 million in fiscal 2019 and $0.4 million in fiscal 2018. 401(k) Retirement Plan . The Dorman Products, Inc. 401(k) Retirement Plan and Trust (the “401(k) Plan”) is a defined contribution profit sharing and 401(k) plan covering substantially all of our employees as of December 28, 2019. Annual contributions under the 401(k) Plan are determined by the Compensation Committee of our Board of Directors. Total expense related to the 401(k) Plan was $3.1 million in fiscal 2019, $4.3 million in fiscal 2018 and $2.7 million in fiscal 2017. At December 28, 2019, the 401(k) Plan held 218,728 shares of our common stock. Common Stock Repurchases. We periodically repurchase, at the then current market price, and cancel common stock issued to 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. During fiscal 2019 our Board of Directors approved the repurchase and cancellation of 22,380 shares of our common stock for $1.9 million at an average price of $87.26 per share. During fiscal 2018, our Board of Directors approved the repurchase and cancellation of 26,280 shares of our common stock for $ 2.0 million at an average price of $ 74.79 per share. During fiscal 2017 , our Board of Directors approved the repurchase and cancellation of 19,110 shares of our common stock for $ 1.4 million at an average price of $ 73.34 per share. Share Repurchase Program . On December 12, 2013 we announced that our Board of Directors authorized a share repurchase program, authorizing the repurchase of up to $10 million of our outstanding common stock by the end of 2014. Through several expansions and extensions, our Board of Directors has expanded the program up to $400 million and extended the program 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. We repurchased 499,564 common shares for $39.4 million at an average price of $78.84 under this program during fiscal 2019. We repurchased 622,223 common shares for $43.4 million at an average price of $69.73 under this program during fiscal 2018. We repurchased 1,006,365 common shares for $74.7 million at an average price of $74.26 under this program during fiscal 2017. At December 28, 2019, $143.9 million was available for repurchase under this program.

Earnings Per Share

Earnings Per Share	12 Months Ended
	Dec. 28, 2019
Earnings Per Share [Abstract]
Earnings Per Share	14. Earnings Per Share Basic earnings per share was calculated by dividing our net income by the weighted average number of common shares outstanding during the period, excluding unvested restricted stock which is 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 approximately 92,000 shares, 116,000 shares and 106,000 shares were excluded from the calculation of diluted earnings per share as of December 28, 2019, December 29, 2018 and December 30, 2017, 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: (in thousands, except per share data) 2019 2018 2017 Numerator: Net income $ 83,762 $ 133,602 $ 106,599 Denominator: Weighted average basic shares outstanding 32,606 33,097 33,964 Effect of compensation awards 82 110 88 Weighted average diluted shares outstanding 32,688 33,207 34,052 Earnings Per Share: Basic $ 2.57 $ 4.04 $ 3.14 Diluted $ 2.56 $ 4.02 $ 3.13

Business Segments

Business Segments	12 Months Ended
	Dec. 28, 2019
Segment Reporting [Abstract]
Business Segments	15. Business Segments We have determined that our business comprises a single During fiscal 2019, fiscal 2018 and fiscal 2017, four of our customers (Advance Auto Parts, Inc., AutoZone, Inc., Genuine Parts Co. – NAPA, and O’Reilly Automotive, Inc.) each accounted for more than 10% of net sales and in the aggregate accounted for 66% of net sales in fiscal 2019, 63% in fiscal 2018 and 61% in fiscal 2017. Net sales to countries outside the United States, primarily to Canada and Mexico, and to a lesser extent into Europe, the Middle East, and Australia in fiscal 2019, fiscal 2018 and fiscal 2017 were $61.4 million, $60.5 million and $55.8 million, respectively.

Quarterly Results of Operations

Quarterly Results of Operations (Unaudited)	12 Months Ended
	Dec. 28, 2019
Quarterly Financial Information Disclosure [Abstract]
Quarterly Results of Operations (Unaudited)	16. Quarterly Results of Operations (Unaudited) The following is a summary of the unaudited quarterly Results of Operations for the fiscal years ended December 28, 2019 and December 29, 2018: First Quarter Second Quarter Third Quarter Fourth Quarter (in thousands, except per share amounts) 2019 Net sales $ 243,791 $ 254,175 $ 253,796 $ 239,567 Income from operations 29,742 27,223 26,963 21,900 Net income 23,407 21,499 21,308 17,548 Diluted earnings per share 0.71 0.66 0.65 0.54 First Quarter Second Quarter Third Quarter Fourth Quarter (in thousands, except per share amounts) 2018 Net sales* $ 227,262 $ 238,147 $ 247,954 $ 260,341 Income from operations* 39,994 42,780 43,733 44,637 Net income 30,647 34,339 34,017 34,599 Diluted earnings per share* 0.93 1.03 1.03 1.05 *Quarterly information does not add to year to date information due to rounding

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 28, 2019
Subsequent Events [Abstract]
Subsequent Events	17. Subsequent Events On January 2, 2020, we acquired the remaining 60% of the outstanding stock of Power Train Industries (“PTI”), a privately-held supplier of parts to the automotive aftermarket, based in Reno, Nevada. The purchase price was $18.2 million, subject to working capital adjustments, and was accounted for as a business combination. We will consolidate PTI’s results beginning in the first quarter of 2020. Prior to the acquisition date, we accounted for our 40% interest in PTI, which was acquired in 2016, as an equity-method investment.

Schedule II_ Valuation and Qual

Schedule II: Valuation and Qualifying Accounts	12 Months Ended
	Dec. 28, 2019
Valuation And Qualifying Accounts [Abstract]
Schedule II: Valuation and Qualifying Accounts	SCHEDULE II: Valuation and Qualifying Accounts For the Year Ended (in thousands) December 28, 2019 December 29, 2018 December 30, 2017 Allowance for doubtful accounts: Balance, beginning of period $ 982 $ 1,656 $ 1,345 Provision 39 (570 ) 299 Charge-offs (64 ) (151 ) 12 Acquisitions and other - 47 - Balance, end of period $ 957 $ 982 $ 1,656 Allowance for customer credits: Balance, beginning of period $ 90,596 $ 95,537 $ 98,650 Provision 274,243 203,677 187,422 Charge-offs (258,889 ) (208,665 ) (193,753 ) Acquisitions and other - 47 3,218 Balance, end of period $ 105,950 $ 90,596 $ 95,537

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 28, 2019
Accounting Policies [Abstract]
Principles of Consolidation	Principles of Consolidation . The Consolidated Financial Statements include our accounts and the accounts of our wholly-owned subsidiaries. All material intercompany accounts and transactions have been eliminated in consolidation.
Use of Estimates in the Preparation of Financial Statements	Use of Estimates in the Preparation of Financial Statements . The preparation of financial statements in accordance with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.
Reclassifications	Reclassifications . Certain prior year amounts have been reclassified to conform with the current-year presentation.
Cash and Cash Equivalents	Cash and Cash Equivalents . We consider all highly liquid short-term investments with original maturities of three months or less to be cash equivalents.
Sales of Accounts Receivable	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 programs were accounted for as sales of accounts receivable and were removed from our Consolidated Balance Sheet at the time of the sales transactions. During fiscal 2019, fiscal 2018 and fiscal 2017, we sold $676.4 million, $604.7 million and $582.9 million, respectively, pursuant to these programs. If receivables had not been sold, $437.9 million and $378.5 million of additional receivables would have been outstanding at December 28, 2019 and December 29, 2018, respectively, based on standard payment terms. Selling, general and administrative expenses include $16.7 million, $14.5 million and $11.4 million in fiscal 2019, fiscal 2018 and fiscal 2017, respectively, of financing costs associated with these accounts receivable sales programs.
Inventories	Inventories . Inventories are stated at the lower of cost or net realizable value. Cost is determined by the first-in, first-out method. Inventories include the cost of material, freight, direct labor and overhead utilized in the processing of our products. We provide reserves for discontinued and excess inventory based upon historical demand, forecasted usage, estimated customer requirements and product line updates.
Property, Plant and Equipment	Property, Plant and Equipment . Property, plant and equipment are recorded at cost and depreciated over their estimated useful lives, which range from three to thirty-nine years, using the straight-line method for financial statement reporting purposes and accelerated methods for income tax purposes. The costs of maintenance and repairs are expensed as incurred. Renewals and betterments are capitalized. Gains and losses on disposals are included in operating results. Estimated useful lives by major asset category are as follows: Buildings and building improvements 10 to 39 years Machinery, equipment and tooling 3 to 7 years Software and computer equipment 3 to 10 years Furniture, fixtures and leasehold improvements 3 to 7 years
Long-Lived Assets Including Goodwill and Other Acquired Intangible Assets	Long-Lived Assets Including Goodwill and Other Acquired Intangible Assets . Long-lived assets, including property, plant, and equipment and amortizable identifiable intangibles, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset or asset group may not be recoverable. The impairment review is a two-step process. First, recoverability is measured by comparing the carrying amount of an asset to the estimated undiscounted future cash flows expected to be generated by the asset. If the carrying amount exceeds the estimated undiscounted future cash flows, the second step of the impairment test is performed and an impairment charge is recognized in the amount by which the carrying amount of the asset exceeds its fair value. Assets to be disposed of would be separately presented in the balance sheet and reported at the lower of the carrying amount or fair value less costs to sell, and are no longer depreciated. The assets and liabilities of a disposal group classified as held for sale would be presented separately in the appropriate asset and liability sections of the balance sheet. Goodwill is reviewed for impairment on an annual basis or whenever events or changes in circumstances indicate the carrying value of the goodwill may be impaired. In regards to the annual test, we have 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. If we determine it is not more likely than not that the fair value of a reporting unit is less than its carrying amount, then performing the two-step impairment test is unnecessary.
Purchase Accounting	Purchase Accounting . The purchase price of an acquired business is allocated to the underlying tangible and intangible assets acquired and liabilities assumed based upon their respective fair market values, with the excess recorded as goodwill. Such fair market value assessments require judgments and estimates which may change over time and may cause the final amounts to differ materially from their original estimates. These adjustments to fair value assessments are recorded to goodwill over the purchase price allocation period which cannot exceed twelve months from the date of acquisition.
Other Assets	Other Assets . Other assets include primarily long-term core inventory, deposits, and equity method investments. Certain products we sell contain parts that can be recycled, or as more commonly referred to in our industry, remanufactured. We refer to these parts as cores. A used core is remanufactured and sold to the customer as a replacement for a unit inside a vehicle. Customers and end-users that purchase remanufactured products will generally return the used core to us, which we then use in the remanufacturing process to make another finished good. Our core inventory consists of used cores purchased and held in our facilities, used cores that are in the process of being returned from our customers and end-users, and remanufactured cores held in finished goods inventory at our facilities. Our products that utilize a core primarily include instrument clusters, hybrid batteries, radios, and climate control modules. Long-term core inventory was $22.8 million and $28.1 million as of December 28, 2019 and December 29, 2018, respectively. Long-term core inventory is recorded at the lower of cost or net realizable value. Cost is determined based on actual purchases of core inventory. We believe that the most appropriate classification of core inventory is a long-term asset. According to guidance provided under the Financial Accounting Standards Board (“FASB”) Accounting Standards Codification(“ASC”), current assets are defined as “assets or resources commonly identified as those which are reasonably expected to be realized in cash or sold or consumed during the normal operating cycle of the business.” The determination of the long-term classification is based on our view that the value of the cores is not expected to be consumed or realized in cash during our normal annual operating cycle. We also have investments that we account for according to the equity method of accounting. The total book value of these investments was $ 19.3 million as of December 28, 2019 and $ 18.4 million as of December 29, 2018 , and these investments provided us $ 3.2 million and $ 2.2 million of income during fiscal 2019 and fiscal 2018 , respectively . Additionally, in fiscal 2018 we purchased an investment that we account for according to the cost method of accounting. The book value of this investment was $ 5.0 million as of December 28, 2019 .
Other Accrued Liabilities	Other Accrued Liabilities. Other accrued liabilities include primarily accrued commissions, accrued income taxes, insurance liabilities, product warranties, and other current liabilities. We warrant our products against certain defects in material and workmanship when used as designed on the vehicle on which it was originally installed. We offer a limited lifetime warranty on most of our products. Our warranty limits the end-user’s remedy to the repair or replacement of the part that is defective. Product warranty reserves, which were $0.6 million as of December 28, 2019 and December 29, 2018, respectively, are based upon actual experience and forecasts using the best historical and current claim information available. Provisions and payments related to product warranty reserves were not material in fiscal 2019, fiscal 2018 or fiscal 2017.
Revenue Recognition and Accrued Customer Rebates and Returns	Revenue Recognition and Accrued Customer Rebates and Returns . 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 record estimates for cash discounts, product returns, promotional rebates, core return deposits, and other discounts in the period of the sale ("Customer Credits"). The provision for Customer Credits is recorded as a reduction from gross sales and reserves for Customer Credits are shown as an increase of accrued customer rebates and returns, which is included in current liabilities. Actual Customer Credits have not differed materially from estimated amounts. 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. As noted above, Customer Credits include core return deposits which are an estimate of the amount we believe we will refund to our customers when used cores are returned to us. The price we invoice to customers for remanufactured cores contain both the amount we charge to remanufacture the part and a deposit for the core. We charge a core deposit to encourage the customer to return the used core to us so that it can be used in our remanufacturing process. We allow our customers up to twenty-four months to return the used core to us. Core return deposits are reserved based on the expected deposits to be issued to customers based on historical returns.
Revision of Prior Period Financial Statements	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 FASB Accounting Standards Update (“ASU”) No. 2014-09, Revenue from Contracts with Customers, related to the balance sheet classification of accrued customer rebates and returns that are recognized in connection with sales of our products. We adopted this ASU on December 31, 2017, the beginning of our 2018 fiscal year. We previously recorded accrued customer rebates and returns that were expected to be issued as credits to our customers as a valuation account which offset accounts receivable. Accrued customer rebates and returns are now recorded as a current liability. Previously issued comparative financial statements, which were revised to correct the error noted above, are presented “As Revised” in the tables presented in the following footnotes. December 29, 2018 (in thousands) As Previously Reported Adjustment As Revised Revised Consolidated Balance Sheet Amounts: Assets Accounts receivable, net $ 310,114 $ 90,549 $ 400,663 Total current assets $ 629,728 $ 90,549 $ 720,277 Total assets $ 887,557 $ 90,549 $ 978,106 Liabilities and shareholders' equity Accrued customer rebates and returns $ 6,338 $ 90,549 $ 96,887 Total current liabilities $ 141,590 $ 90,549 $ 232,139 Total liabilities and shareholders' equity $ 887,557 $ 90,549 $ 978,106 Fiscal Year Ended December 29, 2018 (in thousands) As Previously Reported Adjustment As Revised Revised Consolidated Statement of Cash Flows from Operating Activities Amounts: Accounts receivable $ (66,403 ) $ 4,990 $ (61,413 ) Accrued customer rebates and returns $ — $ (5,173 ) $ (5,173 ) Accrued compensation and other liabilities $ 4,318 $ 183 $ 4,501 Net cash used in operating activities $ 78,112 $ — $ 78,112 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 Statement of Operations or our Consolidated Statements of Shareholders’ Equity in any period presented.
Research and Development	Research and Development . Research and development costs are expensed as incurred. Research and development costs totaling $21.0 million in fiscal 2019, $20.1 million in fiscal 2018 and $20.0 million in fiscal 2017 have been recorded in selling, general and administrative expenses in the Consolidated Statements of Operations.
Stock-Based Compensation	Stock-Based Compensation . At December 28, 2019 and December 29, 2018, we had awards outstanding under two stock-based employee compensation plans, which are described more fully in Note 13, Capital Stock. We record compensation expense for all awards granted. The value of restricted stock issued is based on the fair value of our common stock on the grant date. For performance-based restricted stock awards tied to growth and adjusted pre-tax income, compensation costs related to the stock 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 as of the reporting date. The fair value of performance based restricted stock, for which the performance measure is total shareholder return, was determined using the Monte Carlo simulation model. The fair value of stock options granted was determined using the Black-Scholes option valuation model.
Income Taxes	Income Taxes . We follow the asset and liability method of accounting for deferred income taxes. Deferred tax assets and liabilities are determined based on the difference between the financial statement and tax bases of assets and liabilities. Deferred tax assets or liabilities at the end of each period are determined using the enacted tax rate expected to be in effect when taxes are actually paid or recovered. Unrecognized income tax benefits represent income tax positions taken on income tax returns that have not been recognized in the consolidated financial statements. The Company recognizes the benefit of an income tax position only if it is more likely than not (greater than 50%) that the tax position will be sustained upon tax examination, based solely on the technical merits of the tax position. Otherwise, no benefit is recognized. The tax benefits recognized are measured based on the largest benefit that has a greater than 50% likelihood of being realized upon ultimate settlement. Additionally, we accrue interest and related penalties, if applicable, on all tax exposures for which reserves have been established consistent with jurisdictional tax laws. Interest and penalties are classified as income tax expense in the Consolidated Statements of Operations. The Company does not anticipate material changes in the amount of unrecognized income tax benefits over the next year.
Concentrations of Risk	Concentrations of Risk . Financial instruments that potentially subject us to concentrations of credit risk consist primarily of cash equivalents and accounts receivable. All cash equivalents are managed within established guidelines which limit the amount which may be invested with one issuer. A significant percentage of our accounts receivable have been, and will continue to be, concentrated among a relatively small number of automotive retailers and warehouse distributors in the United States. Our largest customer s accounted for 80% of net accounts receivable as of December 28, 2019 and 76% o f net accounts receivable as of December 29, 2018 , respectively . We continually monitor the credit terms and credit limits to these and other customers. In fiscal 2019 , approximately 79% of our products were purchased from suppliers located in a variety of foreign countries, with the largest portion coming from China.
Fair Value Disclosures	Fair Value Disclosures . The carrying value of financial instruments such as cash and cash equivalents, accounts receivable, accounts payable, and other current assets and liabilities approximate their fair value based on the short-term nature of these instruments. Additionally, the fair value of assets acquired and liabilities assumed are determined at the date of acquisition. We did not hold any foreign currency forward contracts at December 28, 2019 or December 29, 2018.
New and Recently Adopted Accounting Pronouncements	On December 30, 2018, the beginning of our 2019 fiscal year, we adopted ASU No. 2016-02, Leases, which replaces existing lease guidance. The ASU is intended to provide enhanced transparency and comparability by requiring lessees to record right-of-use assets and corresponding lease liabilities on the balance sheet. The new guidance will continue to classify leases as either finance or operating, with classification affecting the pattern of expense recognition in the statement of operations. Additionally, in August 2018, the FASB issued ASU 2018-11, Targeted Improvements to ASC 842, which includes an option to not restate comparative periods in transition and elect to use the effective date of ASC 842 as the date of initial application of transition. We adopted the standard using the modified retrospective approach and adoption resulted in right-of-use assets of $36.3 million and lease liabilities of $37.9 m In January 2017, the FASB issued ASU 2017-04, Simplifying the Test for Goodwill Impairment In June 2018, the FASB issued ASU 2018-07, Improvements to Nonemployee Share-Based Payment Accounting 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. This ASU removes certain exceptions for recognizing deferred taxes for investments, performing intraperiod allocation and calculating income taxes in 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 . H owever, at this time we do not believe this new guidance will have a material impact on our consolidated financial statements and related disclosures.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 28, 2019
Estimated Useful Lives by Major Asset	Estimated useful lives by major asset category are as follows: Buildings and building improvements 10 to 39 years Machinery, equipment and tooling 3 to 7 years Software and computer equipment 3 to 10 years Furniture, fixtures and leasehold improvements 3 to 7 years
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, are presented “As Revised” in the tables presented in the following footnotes. December 29, 2018 (in thousands) As Previously Reported Adjustment As Revised Revised Consolidated Balance Sheet Amounts: Assets Accounts receivable, net $ 310,114 $ 90,549 $ 400,663 Total current assets $ 629,728 $ 90,549 $ 720,277 Total assets $ 887,557 $ 90,549 $ 978,106 Liabilities and shareholders' equity Accrued customer rebates and returns $ 6,338 $ 90,549 $ 96,887 Total current liabilities $ 141,590 $ 90,549 $ 232,139 Total liabilities and shareholders' equity $ 887,557 $ 90,549 $ 978,106 Fiscal Year Ended December 29, 2018 (in thousands) As Previously Reported Adjustment As Revised Revised Consolidated Statement of Cash Flows from Operating Activities Amounts: Accounts receivable $ (66,403 ) $ 4,990 $ (61,413 ) Accrued customer rebates and returns $ — $ (5,173 ) $ (5,173 ) Accrued compensation and other liabilities $ 4,318 $ 183 $ 4,501 Net cash used in operating activities $ 78,112 $ — $ 78,112 (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)	12 Months Ended
	Dec. 28, 2019
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 $ 14,840 8-12 Tradenames 5,600 15 Total $ 20,440
Summary of Preliminary Fair Value of Total Consideration	The following table summarizes the preliminary fair value of the total consideration at October 26, 2017: (in thousands) Total Acquisition Date Fair Value Cash consideration (net of $3.3 million cash received) $ 56,859 Contingent cash consideration 7,982 Seller liability assumed 896 Working capital adjustment 1,486 Total consideration assigned to net assets acquired $ 67,223
Summary of Preliminary Fair Values of Assets Acquired and Liabilities Assumed	The following table summarizes the fair values of the assets acquired and liabilities assumed as of October 26, 2017 (in thousands): (in thousands) October 26, 2017 (As initially reported) Measurement period adjustments October 26, 2017 (As adjusted) Current assets (net of $3.3 million cash received) $ 21,756 $ 90 $ 21,846 Property, plant and equipment 1,615 - 1,615 Intangible assets 20,440 - 20,440 Goodwill 35,624 (193 ) 35,431 Total assets acquired 79,435 (103 ) 79,332 Current liabilities 5,691 (50 ) 5,641 Long-term liabilities 6,468 - 6,468 Total liabilities assumed 12,159 (50 ) 12,109 Net assets acquired $ 67,276 $ (53 ) $ 67,223
Flight Systems Automotive Group LLC [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 $ 3,400 8 Tradenames 460 5 Other 240 5 Total $ 4,100

Inventories (Tables)

Inventories (Tables)	12 Months Ended
	Dec. 28, 2019
Inventory Disclosure [Abstract]
Inventories	Inventories were as follows: (in thousands) December 28, 2019 December 29, 2018 Bulk product $ 114,308 $ 122,111 Finished product 161,866 144,897 Packaging materials 4,639 3,496 Total $ 280,813 $ 270,504

Property, Plant and Equipment (

Property, Plant and Equipment (Tables)	12 Months Ended
	Dec. 28, 2019
Property Plant And Equipment [Abstract]
Property, Plant and Equipment	Property, plant and equipment include the following: (in thousands) December 28, 2019 December 29, 2018 Buildings $ 37,513 $ 34,943 Machinery, equipment and tooling 126,663 115,656 Furniture, fixtures and leasehold improvements 5,308 6,199 Software and computer equipment 80,397 79,349 Total 249,881 236,147 Less-accumulated depreciation and amortization (148,044 ) (137,500 ) Property, plant and equipment, net $ 101,837 $ 98,647

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 28, 2019
Leases [Abstract]
Summary of Lease Expense	The following table summarizes the lease expense for the year ended December 28, 2019 : (in thousands) December 28, 2019 Operating lease expense $ 7,362 Short-term lease expense 4,547 Total lease expense $ 11,909
Summary of Supplemental Balance Sheet Information Related to Operating Leases	Supplemental balance sheet information related to our operating leases is as follows: (in thousands) December 28, 2019 Operating lease right-of-use assets $ 32,198 Other accrued liabilities $ 5,348 Long-term operating lease liabilities 29,730 Total operating lease liabilities $ 35,078 Weighted average remaining lease term (years) 10.83 Weighted average discount rate 6.32 %
Summary of Maturities of Operating Lease Liabilities	The following table summarizes the maturities of our lease liabilities for all operating leases as of December 28, 2019: (in thousands) December 28, 2019 2020 $ 6,935 2021 4,977 2022 4,904 2023 3,388 2024 3,452 2025 and thereafter 21,514 Total lease payments 45,170 Less: Imputed interest (10,092 ) Present value of lease liabilities $ 35,078
Summary of Minimum Future Rental Payments under Operating Leases	For the year ended December 29, 2018, minimum rental payments under operating leases were recognized on a straight-line basis over the term of the lease including any periods of free rent. Rent expense for operating leases, including payments for short-term equipment and storage rentals, was $6.9 million in fiscal 2018 and $5.7 million in fiscal 2017. Minimum future rental payments required under operating leases in effect as of December 29, 2018 were as follows: (in thousands) December 29, 2018 2019 $ 5,489 2020 5,416 2021 4,972 2022 4,599 2023 3,013 2024 and thereafter 24,297 Total rental payments $ 47,786

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	12 Months Ended
	Dec. 28, 2019
Goodwill And Intangible Assets Disclosure [Abstract]
Schedule of Goodwill	Goodwill Goodwill included the following: (in thousands) December 28, 2019 December 29, 2018 Balance at beginning of period $ 72,606 $ 65,999 Goodwill acquired - 6,800 Measurement period adjustment 1,852 (193 ) Balance at end of period $ 74,458 $ 72,606
Schedule of Intangible Assets	Intangible Assets Intangible assets, subject to amortization, included the following: December 28, 2019 December 29, 2018 (dollars in thousands) Weighted Average Amortization Period (years) Gross Carrying Value Accumulated Amortization Net Carrying Value Gross Carrying Value Accumulated Amortization Net Carrying Value Intangible assets subject to amortization Tradenames 12.3 $ 6,060 $ 975 $ 5,085 $ 7,590 $ 516 $ 7,074 Customer relationships 8.0 20,450 4,698 15,752 20,130 2,582 17,548 Technology 12.0 367 74 293 367 49 318 Other 3.7 240 65 175 240 16 224 Total $ 27,117 $ 5,812 $ 21,305 $ 28,327 $ 3,163 $ 25,164
Schedule of Estimated Future Amortization Expense	The estimated future amortization expense for intangible assets is summarized as follows: (in thousands) 2020 $ 2,674 2021 2,674 2022 2,674 2023 2,626 2024 2,530 Thereafter 8,127 Total $ 21,305

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 28, 2019
Income Tax Disclosure [Abstract]
Components of Income Tax Provision (Benefit)	The components of the income tax provision (benefit) are as follows: (in thousands) 2019 2018 2017 Current: Federal $ 19,090 $ 33,362 $ 56,641 State 2,091 2,618 8,293 Foreign (194 ) 1,611 379 20,987 37,591 65,313 Deferred: Federal 2,084 1,398 4,582 State (280 ) 186 343 Foreign (746 ) (1,642 ) (249 ) 1,058 (58 ) 4,676 Total $ 22,045 $ 37,533 $ 69,989
Reconciliation of Income Taxes at Statutory Tax Rate to Company's Effective Tax Rate	The following is a reconciliation of income taxes at the statutory tax rate to the Company's effective tax rate: 2019 2018 2017 Federal taxes at statutory rate 21.0 % 21.0 % 35.0 % State taxes, net of federal tax benefit 1.3 1.3 3.4 Research and development tax credit (0.5 ) (0.4 ) (0.3 ) Federal permanent items (0.3 ) (0.1 ) (0.4 ) Tax reform — — 2.5 Effect of foreign operations (1.1 ) (0.2 ) (0.1 ) Other 0.4 0.3 (0.5 ) Effective tax rate 20.8 % 21.9 % 39.6 %
Change in Unrecognized Tax Benefits	The following table summarizes the change in unrecognized tax benefits for the three years ended December 28, 2019: (in thousands) 2019 2018 2017 Balance at beginning of year $ 2,390 $ 2,301 $ 3,567 Reductions due to lapses in statutes of limitations (200 ) (95 ) (181 ) Reductions due to tax positions settled — (368 ) (4,543 ) Reductions due to reversals of prior year positions (28 ) (4 ) — Additions based on tax positions taken during the prior period — — 3,005 Additions based on tax positions taken during the current period 139 556 453 Balance at end of year $ 2,301 $ 2,390 $ 2,301
Reconciliation of Deferred Tax Assets and Liabilities	Deferred income taxes result from timing differences in the recognition of revenue and expense for tax and financial statement purposes. The sources of temporary differences are as follows: (in thousands) December 28, 2019 December 29, 2018 Assets: Inventories $ 9,545 $ 9,006 Accounts receivable 10,695 11,052 Operating lease liability 7,273 - Accrued expenses 1,974 1,792 Foreign tax credits 844 1,050 Total deferred tax assets 30,331 22,900 Valuation allowance (844 ) (1,050 ) Net deferred tax assets 29,487 21,850 Liabilities: Depreciation 10,296 9,094 Goodwill and intangible assets 11,742 11,310 Operating lease right of use asset 6,656 - Other 416 12 Gross deferred tax liabilities 29,110 20,416 Net deferred tax assets $ 377 $ 1,434

Revenue Recognition (Tables)

Revenue Recognition (Tables)	12 Months Ended
	Dec. 28, 2019
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. (in thousands) 2019 2018 2017 Powertrain $ 395,975 $ 393,979 $ 374,372 Chassis 297,350 278,584 238,239 Automotive Body 251,506 256,344 245,869 Hardware 46,498 44,798 44,741 Net Sales $ 991,329 $ 973,705 $ 903,221 (in thousands) 2019 2018 2017 Net Sales to U.S. Customers $ 929,908 $ 913,181 $ 847,394 Net Sales to Non-U.S. Customers 61,421 60,524 55,827 Net Sales $ 991,329 $ 973,705 $ 903,221

Capital Stock (Tables)

Capital Stock (Tables)	12 Months Ended
	Dec. 28, 2019
Schedule of Weighted Average Valuation Assumptions Used to Calculate Fair Value Granted	The following table summarizes the weighted average valuation assumptions used to calculate the fair value of options granted: 2019 2018 2017 Expected dividend yield 0 % 0 % 0 % Expected stock price volatility 28 % 27 % 27 % Risk-free interest rate 2.3 % 2.6 % 1.5 % Expected life of options 5.4 years 3.0 years 3.0 years
Summary of Restricted Stock Activity	The following table summarizes our restricted stock activity for the three years ended December 28, 2019: Shares Weighted Average Price Balance at December 31, 2016 145,363 $ 49.22 Granted 70,611 $ 78.27 Vested (56,953 ) $ 56.03 Cancelled (5,294 ) $ 51.56 Balance at December 30, 2017 153,727 $ 59.94 Granted 89,798 $ 73.51 Vested (45,707 ) $ 62.56 Cancelled (27,081 ) $ 75.39 Balance at December 29, 2018 170,737 $ 63.94 Granted 92,396 $ 81.92 Vested (41,586 ) $ 55.72 Cancelled (44,056 ) $ 58.03 Balance at December 28, 2019 177,491 $ 76.70
Summary of Stock Option Activity	The following table summarizes our stock option activity for the three years ended December 28, 2019: Shares Option Price per Share Weighted Average Price Weighted Average Remaining Terms (years) Aggregate Intrinsic Value Balance at December 31, 2016 101,084 $5.67 – $53.32 $ 29.52 Granted 58,024 $69.02 – $82.59 $ 78.58 Exercised (32,751 ) $6.90 – $41.59 $ 7.69 Cancelled (3,810 ) $41.59 – $78.64 $ 56.72 Balance at December 30, 2017 122,547 $5.67 – $82.59 $ 57.74 Granted 81,995 $68.93 – $82.94 $ 73.84 Exercised (15,113 ) $5.67 – $78.64 $ 39.38 Cancelled (960 ) $ 72.55 $ 72.55 Balance at December 29, 2018 188,469 $7.74 – $82.94 $ 66.14 Granted 44,025 $73.72 – $84.93 $ 81.84 Exercised (38,009 ) $7.74 – $78.76 $ 58.96 Cancelled (12,773 ) $41.59 – $82.94 $ 75.52 Balance at December 28, 2019 181,712 $41.59 – $84.93 $ 70.78 3.8 $ 1,308,808 Options exercisable at December 28, 2019 63,432 $41.59 – $82.94 $ 62.39 2.3 $ 897,145
Summary of Information Concerning Currently Outstanding and Exercisable Options	The following table summarizes information concerning currently outstanding and exercisable options at December 28, 2019: Options Outstanding Options Exercisable Range of Exercise Price Number Outstanding Weighted Average Remaining Contractual Life (years) Weighted Average Exercise Price Number Exercisable Weighted Average Exercise Price $41.59 - $61.13 38,848 1.3 $ 45.94 29,136 $ 45.94 $61.14 - $73.13 52,413 3.9 $ 71.89 13,762 $ 71.68 $73.14 - $78.70 24,654 3.4 $ 77.60 9,650 $ 78.64 $78.71 - $82.31 35,803 5.2 $ 80.65 6,871 $ 78.76 $82.32 - $84.93 29,994 5.6 $ 83.66 4,013 $ 82.83 Balance at December 28, 2019 181,712 3.8 $ 70.78 63,432 $ 62.39
Performance Restricted Stock [Member]
Schedule of Weighted Average Valuation Assumptions Used to Calculate Fair Value Granted	The following table summarizes the weighted average valuation assumptions used to calculate the fair value of total shareholder return performance restricted stock granted: 2019 Share price $ 82.03 Expected dividend yield 0.0 % Expected stock price volatility 27.7 % Risk-free interest rate 2.5 % Expected life 2.8 years

Earnings Per Share (Tables)

Earnings Per Share (Tables)	12 Months Ended
	Dec. 28, 2019
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: (in thousands, except per share data) 2019 2018 2017 Numerator: Net income $ 83,762 $ 133,602 $ 106,599 Denominator: Weighted average basic shares outstanding 32,606 33,097 33,964 Effect of compensation awards 82 110 88 Weighted average diluted shares outstanding 32,688 33,207 34,052 Earnings Per Share: Basic $ 2.57 $ 4.04 $ 3.14 Diluted $ 2.56 $ 4.02 $ 3.13

Quarterly Results of Operatio_2

Quarterly Results of Operations (Unaudited) (Tables)	12 Months Ended
	Dec. 28, 2019
Quarterly Financial Information Disclosure [Abstract]
Summary of Quarterly Results of Operations	The following is a summary of the unaudited quarterly Results of Operations for the fiscal years ended December 28, 2019 and December 29, 2018: First Quarter Second Quarter Third Quarter Fourth Quarter (in thousands, except per share amounts) 2019 Net sales $ 243,791 $ 254,175 $ 253,796 $ 239,567 Income from operations 29,742 27,223 26,963 21,900 Net income 23,407 21,499 21,308 17,548 Diluted earnings per share 0.71 0.66 0.65 0.54 First Quarter Second Quarter Third Quarter Fourth Quarter (in thousands, except per share amounts) 2018 Net sales* $ 227,262 $ 238,147 $ 247,954 $ 260,341 Income from operations* 39,994 42,780 43,733 44,637 Net income 30,647 34,339 34,017 34,599 Diluted earnings per share* 0.93 1.03 1.03 1.05 *Quarterly information does not add to year to date information due to rounding

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Additional Information (Detail) $ in Millions	12 Months Ended
	Dec. 28, 2019USD ($)CustomerContract	Dec. 29, 2018USD ($)CustomerContract	Dec. 30, 2017USD ($)
Significant Accounting Policies [Line Items]
Highly liquid short-term investments maturity date	three months or less
Sale of accounts receivable	$ 676.4	$ 604.7	$ 582.9
Additional receivables outstanding if receivables had not been sold	437.9	378.5
Factoring costs associated with the sales of accounts receivable	16.7	14.5	11.4
Long-term core inventory	22.8	28.1
Total book value of equity method investments	19.3	18.4
Income from equity method investments	3.2	2.2
Book value of cost method investments	5
Product warranty reserves	$ 0.6	$ 0.6
Number of largest customers | Customer	4	4
Number of foreign exchange forward contracts outstanding | Contract	0	0
Credit Concentration Risk [Member]
Significant Accounting Policies [Line Items]
Concentration risk percentage	80.00%	76.00%
Supplier Concentration Risk [Member]
Significant Accounting Policies [Line Items]
Concentration risk percentage	79.00%
Selling, General and Administrative Expenses [Member]
Significant Accounting Policies [Line Items]
Research and development costs	$ 21	$ 20.1	$ 20
Minimum [Member]
Significant Accounting Policies [Line Items]
Estimated useful life of Property, Plant and Equipment	3 years
Maximum [Member]
Significant Accounting Policies [Line Items]
Estimated useful life of Property, Plant and Equipment	39 years

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Estimated Useful Lives by Major Asset (Detail)	12 Months Ended
	Dec. 28, 2019
Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life of Property, Plant and Equipment	3 years
Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life of Property, Plant and Equipment	39 years
Buildings and Building Improvements [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life of Property, Plant and Equipment	10 years
Buildings and Building Improvements [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life of Property, Plant and Equipment	39 years
Machinery, Equipment and Tooling [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life of Property, Plant and Equipment	3 years
Machinery, Equipment and Tooling [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life of Property, Plant and Equipment	7 years
Software and Computer Equipment [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life of Property, Plant and Equipment	3 years
Software and Computer Equipment [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life of Property, Plant and Equipment	10 years
Furniture, Fixtures and Leasehold Improvements [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life of Property, Plant and Equipment	3 years
Furniture, Fixtures and Leasehold Improvements [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life of Property, Plant and Equipment	7 years

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Schedule of Revision of Prior Period Financial Statements - Consolidated Balance Sheet (Detail) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018	Dec. 31, 2017
Assets
Accounts receivable, net	$ 391,810	$ 400,663	$ 241,880
Total current assets	754,590	720,277
Total assets	1,041,072	978,106
Liabilities and shareholders' equity
Accrued customer rebates and returns	105,903	96,887	6,522
Total current liabilities	220,502	232,139
Total liabilities and shareholders' equity	$ 1,041,072	978,106
ASU 2014-09 [Member]
Assets
Accounts receivable, net			337,417
Liabilities and shareholders' equity
Accrued customer rebates and returns			102,059
As Previously Reported [Member] | ASU 2014-09 [Member]
Assets
Accounts receivable, net		310,114
Total current assets		629,728
Total assets		887,557
Liabilities and shareholders' equity
Accrued customer rebates and returns		6,338
Total current liabilities		141,590
Total liabilities and shareholders' equity		887,557
Adjustment [Member] | ASU 2014-09 [Member]
Assets
Accounts receivable, net		90,549	95,537
Total current assets		90,549
Total assets		90,549
Liabilities and shareholders' equity
Accrued customer rebates and returns		90,549	$ 95,537
Total current liabilities		90,549
Total liabilities and shareholders' equity		$ 90,549

Summary of Significant Accoun_7

Summary of Significant Accounting Policies - Schedule of Revision of Prior Period Financial Statements - Consolidated Statement of Cash Flows (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Error Corrections And Prior Period Adjustments Restatement [Line Items]
Accounts receivable	$ 8,810	$ (61,413)	$ (5,709)
Accrued customer rebates and returns	9,016	(5,173)
Accrued compensation and other liabilities	(349)	4,501	(6,925)
Net cash used in operating activities	$ 95,306	78,112	$ 94,241
As Previously Reported [Member] | ASU 2014-09 [Member]
Error Corrections And Prior Period Adjustments Restatement [Line Items]
Accounts receivable		(66,403)
Accrued compensation and other liabilities		4,318
Net cash used in operating activities		78,112
Adjustment [Member] | ASU 2014-09 [Member]
Error Corrections And Prior Period Adjustments Restatement [Line Items]
Accounts receivable		4,990
Accrued customer rebates and returns		(5,173)
Accrued compensation and other liabilities		$ 183

New and Recently Adopted Acco_2

New and Recently Adopted Accounting Pronouncements - Additional Information (Detail) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 30, 2018	Dec. 29, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Right-of-use asset	$ 32,198
Lease liabilities	$ 35,078
ASU 2016-02 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Right-of-use asset			$ 36,300
Lease liabilities			$ 37,900
Reclassification of deferred rent and lease incentive liabilities to operating lease right-of-use assets		$ 1,600

Business Acquisitions and Inv_3

Business Acquisitions and Investments - Additional Information (Detail) - USD ($)	Aug. 31, 2018	Oct. 26, 2017	Jan. 06, 2017	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017	Jan. 27, 2017
Business Acquisition [Line Items]
Business acquisition, goodwill				$ 74,458,000	$ 72,606,000	$ 65,999,000
Business acquisition, measurement period adjustments, increase to goodwill				1,852,000	(193,000)
Equity Method Supplier [Member]
Business Acquisition [Line Items]
Equity method investment, ownership percentage							33.00%
Equity method investment, cost							$ 10,000,000
Minimum [Member]
Business Acquisition [Line Items]
Cash flows discounted at rates		15.00%
Maximum [Member]
Business Acquisition [Line Items]
Cash flows discounted at rates		17.00%
Flight Systems Automotive Group LLC [Member]
Business Acquisition [Line Items]
Business acquisition, percentage of outstanding stock acquired	100.00%
Business acquisition, cash paid	$ 27,500,000
Business acquisition, goodwill	7,400,000
Business acquisition, identified intangibles	4,100,000
Business acquisition, other net assets	16,000,000
Business acquisition, accounts receivables	2,000,000
Business acquisition, inventory	8,400,000
Business acquisition, fixed assets	4,400,000
Business acquisition, other assets and liabilities net	$ 1,200,000
Business acquisition, measurement period adjustments, increase to goodwill				1,900,000
Business acquisition, measurement period adjustments, decrease to inventory				700,000
Business acquisition, measurement period adjustments, decrease to identified intangibles				1,200,000
MAS Automotive Distribution Inc [Member]
Business Acquisition [Line Items]
Business acquisition, percentage of outstanding stock acquired		100.00%
Business acquisition, goodwill		$ 35,431,000
Business acquisition, identified intangibles		20,440,000
Business acquisition, fixed assets		1,615,000
Business acquisition, total purchase price consideration		67,223,000
Business acquisition, cash acquired		3,300,000
Net sales, included in consolidated statement of operations				40,300,000
Estimated contingent payments		7,982,000		5,600,000
Business combination maximum contingent consideration payment		$ 11,700,000
Business combination sales thresholds achievement maturity date		2020-12
Payment to former shareholder					1,500,000
Reduction in accrual				(2,300,000)	(7,900,000)
MAS Automotive Distribution Inc [Member] | Selling, General and Administrative Expenses [Member]
Business Acquisition [Line Items]
Estimated contingent payments				300,000
Reduction in accrual				$ (2,600,000)
Ingalls Engineering Company, Inc., [Member]
Business Acquisition [Line Items]
Business acquisition, cash paid			$ 3,100,000
Business acquisition, other net assets			2,000,000
Business acquisition, total purchase price consideration			$ 4,800,000
Business acquisition date			Jan. 6, 2017
Business acquisition, estimated contingent payments			$ 1,700,000
Business acquisition of goodwill and other intangible assets			$ 2,800,000
Ingalls Engineering Company, Inc., [Member] | Selling, General and Administrative Expenses [Member]
Business Acquisition [Line Items]
Reduction in accrual					$ (2,100,000)

Business Acquisitions and Inv_4

Business Acquisitions and Investments - Schedule of Valuation of Intangible Assets Acquired and Related Amortization Periods (Detail) - USD ($) $ in Thousands	Aug. 31, 2018	Oct. 26, 2017
Flight Systems Automotive Group LLC [Member]
Business Acquisition [Line Items]
Valuation,Intangible assets	$ 4,100
Flight Systems Automotive Group LLC [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Valuation,Intangible assets	$ 3,400
Amortization Period (in years)	8 years
Flight Systems Automotive Group LLC [Member] | Tradenames [Member]
Business Acquisition [Line Items]
Valuation,Intangible assets	$ 460
Amortization Period (in years)	5 years
Flight Systems Automotive Group LLC [Member] | Other [Member]
Business Acquisition [Line Items]
Valuation,Intangible assets	$ 240
Amortization Period (in years)	5 years
MAS Automotive Distribution Inc [Member]
Business Acquisition [Line Items]
Valuation,Intangible assets		$ 20,440
MAS Automotive Distribution Inc [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Valuation,Intangible assets		$ 14,840
MAS Automotive Distribution Inc [Member] | Customer Relationships [Member] | Minimum [Member]
Business Acquisition [Line Items]
Amortization Period (in years)		8 years
MAS Automotive Distribution Inc [Member] | Customer Relationships [Member] | Maximum [Member]
Business Acquisition [Line Items]
Amortization Period (in years)		12 years
MAS Automotive Distribution Inc [Member] | Tradenames [Member]
Business Acquisition [Line Items]
Valuation,Intangible assets		$ 5,600
Amortization Period (in years)		15 years

Business Acquisitions and Inv_5

Business Acquisitions and Investments - Summary of Preliminary Fair Value of Total Consideration (Detail) - USD ($) $ in Thousands	Oct. 26, 2017	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Business Acquisition [Line Items]
Cash consideration (net of $3.3 million cash received)			$ 28,040	$ 59,987
MAS Automotive Distribution Inc [Member]
Business Acquisition [Line Items]
Cash consideration (net of $3.3 million cash received)	$ 56,859
Contingent cash consideration	7,982	$ 5,600
Seller liability assumed	896
Working capital adjustment	1,486
Total consideration assigned to net assets acquired	$ 67,223

Business Acquisitions and Inv_6

Business Acquisitions and Investments - Summary of Preliminary Fair Value of Total Consideration (Parenthetical) (Detail) $ in Millions	Oct. 26, 2017USD ($)
MAS Automotive Distribution Inc [Member]
Business Acquisition [Line Items]
Business acquisition, cash received	$ 3.3

Business Acquisitions and Inv_7

Business Acquisitions and Investments - Summary of Preliminary Fair Values of Assets Acquired and Liabilities Assumed (Detail) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017	Oct. 26, 2017
Business Acquisition [Line Items]
Goodwill	$ 74,458	$ 72,606	$ 65,999
MAS Automotive Distribution Inc [Member]
Business Acquisition [Line Items]
Current assets (net of $3.3 million cash received)				$ 21,846
Property, plant and equipment				1,615
Intangible assets				20,440
Goodwill				35,431
Total assets acquired				79,332
Current liabilities				5,641
Long-term liabilities				6,468
Total liabilities assumed				12,109
Net assets acquired				67,223
MAS Automotive Distribution Inc [Member] | As initially reported [Member]
Business Acquisition [Line Items]
Current assets (net of $3.3 million cash received)				21,756
Property, plant and equipment				1,615
Intangible assets				20,440
Goodwill				35,624
Total assets acquired				79,435
Current liabilities				5,691
Long-term liabilities				6,468
Total liabilities assumed				12,159
Net assets acquired				67,276
MAS Automotive Distribution Inc [Member] | Measurement period adjustments [Member]
Business Acquisition [Line Items]
Current assets (net of $3.3 million cash received)				90
Goodwill				(193)
Total assets acquired				(103)
Current liabilities				(50)
Total liabilities assumed				(50)
Net assets acquired				$ (53)

Business Acquisitions and Inv_8

Business Acquisitions and Investments - Summary of Preliminary Fair Values of Assets Acquired and Liabilities Assumed (Parenthetical) (Detail) $ in Millions	Oct. 26, 2017USD ($)
MAS Automotive Distribution Inc [Member]
Business Acquisition [Line Items]
Business acquisition, cash received	$ 3.3

Inventories - Inventories (Deta

Inventories - Inventories (Detail) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018
Inventory Disclosure [Abstract]
Bulk product	$ 114,308	$ 122,111
Finished product	161,866	144,897
Packaging materials	4,639	3,496
Total	$ 280,813	$ 270,504

Property, Plant and Equipment -

Property, Plant and Equipment - Property, Plant and Equipment (Detail) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018
Property, Plant and Equipment [Line Items]
Total	$ 249,881	$ 236,147
Less-accumulated depreciation and amortization	(148,044)	(137,500)
Property, plant and equipment, net	101,837	98,647
Buildings [Member]
Property, Plant and Equipment [Line Items]
Total	37,513	34,943
Machinery, Equipment and Tooling [Member]
Property, Plant and Equipment [Line Items]
Total	126,663	115,656
Furniture, Fixtures and Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Total	5,308	6,199
Software and Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Total	$ 80,397	$ 79,349

Property, Plant and Equipment_2

Property, Plant and Equipment - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Property Plant And Equipment [Abstract]
Depreciation and amortization expenses	$ 25.4	$ 25.4	$ 21.5

Leases - Additional Information

Leases - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Lessee Lease Description [Line Items]
Finance leases	$ 0
Cash paid for operating leases	$ 6,000,000
Rent expense for operating leases, including short-term equipment and storage rentals		$ 6,900,000	$ 5,700,000
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	12 years

Leases - Summary of Lease Expen

Leases - Summary of Lease Expense (Detail) $ in Thousands	12 Months Ended
	Dec. 28, 2019USD ($)
Leases [Abstract]
Operating lease expense	$ 7,362
Short-term lease expense	4,547
Total lease expense	$ 11,909

Leases - Summary of Supplementa

Leases - Summary of Supplemental Balance Sheet Information Related to Operating Leases (Detail) $ in Thousands	Dec. 28, 2019USD ($)
Leases [Abstract]
Operating lease right-of-use assets	$ 32,198
Other accrued liabilities	$ 5,348
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	us-gaap:AccruedLiabilitiesCurrent
Long-term operating lease liabilities	$ 29,730
Total operating lease liabilities	$ 35,078
Weighted average remaining lease term (years)	10 years 9 months 29 days
Weighted average discount rate	6.32%

Leases - Summary of Maturities

Leases - Summary of Maturities of Operating Lease Liabilities (Detail) $ in Thousands	Dec. 28, 2019USD ($)
Leases [Abstract]
2020	$ 6,935
2021	4,977
2022	4,904
2023	3,388
2024	3,452
2025 and thereafter	21,514
Total lease payments	45,170
Less: Imputed interest	(10,092)
Present value of lease liabilities	$ 35,078

Leases - Summary of Minimum Fut

Leases - Summary of Minimum Future Rental Payments under Operating Leases (Detail) $ in Thousands	Dec. 29, 2018USD ($)
Leases [Abstract]
2019	$ 5,489
2020	5,416
2021	4,972
2022	4,599
2023	3,013
2024 and thereafter	24,297
Total rental payments	$ 47,786

Goodwill and Intangible Asset_2

Goodwill and Intangible Assets - Schedule of Goodwill (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018
Goodwill And Intangible Assets Disclosure [Abstract]
Balance at beginning of period	$ 72,606	$ 65,999
Goodwill acquired		6,800
Measurement period adjustment	1,852	(193)
Balance at end of period	$ 74,458	$ 72,606

Goodwill and Intangible Asset_3

Goodwill and Intangible Assets - Schedule of Intangible Assets (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018
Finite Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 27,117	$ 28,327
Accumulated Amortization	5,812	3,163
Net Carrying Value	$ 21,305	25,164
Tradenames [Member]
Finite Lived Intangible Assets [Line Items]
Weighted Average Amortization Period (years)	12 years 3 months 18 days
Gross Carrying Value	$ 6,060	7,590
Accumulated Amortization	975	516
Net Carrying Value	$ 5,085	7,074
Customer Relationships [Member]
Finite Lived Intangible Assets [Line Items]
Weighted Average Amortization Period (years)	8 years
Gross Carrying Value	$ 20,450	20,130
Accumulated Amortization	4,698	2,582
Net Carrying Value	$ 15,752	17,548
Technology [Member]
Finite Lived Intangible Assets [Line Items]
Weighted Average Amortization Period (years)	12 years
Gross Carrying Value	$ 367	367
Accumulated Amortization	74	49
Net Carrying Value	$ 293	318
Other [Member]
Finite Lived Intangible Assets [Line Items]
Weighted Average Amortization Period (years)	3 years 8 months 12 days
Gross Carrying Value	$ 240	240
Accumulated Amortization	65	16
Net Carrying Value	$ 175	$ 224

Goodwill and Intangible Asset_4

Goodwill and Intangible Assets - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Goodwill And Intangible Assets Disclosure [Abstract]
Amortization expense	$ 2.6	$ 2.3	$ 0.5

Goodwill and Intangible Asset_5

Goodwill and Intangible Assets - Schedule of Estimated Future Amortization Expense (Detail) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018
Goodwill And Intangible Assets Disclosure [Abstract]
2020	$ 2,674
2021	2,674
2022	2,674
2023	2,626
2024	2,530
Thereafter	8,127
Net Carrying Value	$ 21,305	$ 25,164

Long-Term Debt - Additional Inf

Long-Term Debt - Additional Information (Detail)	12 Months Ended
	Dec. 28, 2019USD ($)LetterOfCredit	Dec. 30, 2017USD ($)	Jul. 31, 2006USD ($)
Debt Instrument [Line Items]
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	2.45%
Credit facility default percentage	2.00%
Credit facility default amount	$ 0
Borrowings under credit facility	0
Amount available under credit facility, net of letters of credit	99,200,000
Revolving Credit Facility [Member] | Maximum [Member]
Debt Instrument [Line Items]
Line of credit facility incremental 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%

Related Party Transactions - Ad

Related Party Transactions - Additional Information (Detail) $ in Millions	12 Months Ended
	Dec. 28, 2019USD ($)Supplier	Dec. 29, 2018USD ($)	Dec. 30, 2017USD ($)
Related Party Transaction [Line Items]
Total annual rental payments to the partnership / corporation under the lease arrangement	$ 1.6	$ 1.6	$ 1.6
Lease expiration date	Dec. 31, 2022
Lease effective date	Jan. 1, 2018
Minority interests in number of suppliers	two
Purchases from companies	$ 23.2	$ 20.3	$ 16.5
Joint Venture [Member]
Related Party Transaction [Line Items]
Number of suppliers with company partners Joint Venture | Supplier	1

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended			27 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017	Dec. 28, 2019	Dec. 31, 2016
Income Tax Disclosure [Abstract]
U.S. corporate income tax rate	21.00%	21.00%	35.00%
Percentage of expense qualified property placed in service				100.00%
Percentage of dividends received deduction on qualifying dividends paid by foreign subsidiaries				100.00%
Tax on deferred foreign earnings, liquid assets, percentage	15.50%
Tax on deferred foreign earnings, illiquid assets, percentage	8.00%
Defined increments minimum payment period	8 years
Transition tax expense on accumulated earnings and profits of non-U.S. subsidiaries	$ 0
Accumulated earnings and profits of non-U.S. subsidiaries	0			$ 0
Net unrecognized tax benefits	2,301,000	$ 2,390,000	$ 2,301,000	2,301,000	$ 3,567,000
Unrecognized tax benefits which would impact effective tax rate if recognized	2,000,000			2,000,000
Accrued interest and penalties related to unrecognized tax benefits	$ 300,000			$ 300,000

Income Taxes - Components of In

Income Taxes - Components of Income Tax Provision (Benefit) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Current:
Federal	$ 19,090	$ 33,362	$ 56,641
State	2,091	2,618	8,293
Foreign	(194)	1,611	379
Current, Total	20,987	37,591	65,313
Deferred:
Federal	2,084	1,398	4,582
State	(280)	186	343
Foreign	(746)	(1,642)	(249)
Deferred, Total	1,058	(58)	4,676
Total	$ 22,045	$ 37,533	$ 69,989

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of Income Taxes at Statutory Tax Rate to Company's Effective Tax Rate (Detail)	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Federal taxes at statutory rate	21.00%	21.00%	35.00%
State taxes, net of federal tax benefit	1.30%	1.30%	3.40%
Research and development tax credit	(0.50%)	(0.40%)	(0.30%)
Federal permanent items	(0.30%)	(0.10%)	(0.40%)
Tax reform			2.50%
Effect of foreign operations	(1.10%)	(0.20%)	(0.10%)
Other	0.40%	0.30%	(0.50%)
Effective tax rate	20.80%	21.90%	39.60%

Income Taxes - Change in Unreco

Income Taxes - Change in Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance at beginning of year	$ 2,390	$ 2,301	$ 3,567
Reductions due to lapses in statutes of limitations	(200)	(95)	(181)
Reductions due to tax positions settled		(368)	(4,543)
Reductions due to reversals of prior year positions	(28)	(4)
Additions based on tax positions taken during the prior period			3,005
Additions based on tax positions taken during the current period	139	556	453
Balance at end of year	$ 2,301	$ 2,390	$ 2,301

Income Taxes - Reconciliation_2

Income Taxes - Reconciliation of Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018
Assets:
Inventories	$ 9,545	$ 9,006
Accounts receivable	10,695	11,052
Operating lease liability	7,273
Accrued expenses	1,974	1,792
Foreign tax credits	844	1,050
Total deferred tax assets	30,331	22,900
Valuation allowance	(844)	(1,050)
Net deferred tax assets	29,487	21,850
Liabilities:
Depreciation	10,296	9,094
Goodwill and intangible assets	11,742	11,310
Operating lease right of use asset	6,656
Other	416	12
Gross deferred tax liabilities	29,110	20,416
Net deferred tax assets	$ 377	$ 1,434

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail) $ in Millions	12 Months Ended
	Dec. 28, 2019USD ($)
Commitments And Contingencies [Line Items]
Estimated underpayments of duties amount	$ 2.8
Cost of Goods Sold [Member]
Commitments And Contingencies [Line Items]
Estimated underpayments of duties amount	2.4
Selling, General and Administrative Expenses [Member]
Commitments And Contingencies [Line Items]
Estimated underpayments of duties amount	$ 0.4

Revenue Recognition - Additiona

Revenue Recognition - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018
Revenue From Contract With Customer [Line Items]
Revenue, performance obligation, description of good or service	We are a supplier of replacement parts and fasteners for passenger cars, light trucks, and heavy duty trucks in the automotive aftermarket. We group our products into four major classes: power-train, automotive body, chassis, and hardware
Revenue, performance obligation, description of warranty	We warrant our products against certain defects in material and workmanship when used as designed on the vehicle on which it was originally installed. We offer a limited lifetime warranty on most of our products. Our warranty limits the customer’s remedy to the repair or replacement of the part that is defective.
Maximum credit terms allow to customers	1 year
Revenue, performance obligation satisfy, transfer of control goods or sevices, description	We identify the transaction price as the amount of consideration including variable consideration that we expect to be entitled in exchange for transferring control of goods and/or services to our customers.
Revenue, performance obligation satisfy, method of base, description	We allocate the transaction price to each performance obligation on the basis of the amount of consideration to which we expect to be entitled in exchange for satisfying each performance obligation.
Revenue, performance obligation, description of timing	We recognize revenue when we satisfy a performance obligation by transferring control of the promised goods.
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
Maximum [Member]
Revenue From Contract With Customer [Line Items]
Customer purchase order duration of contract	1 year
Customer pays for good or service future duration	1 year
Expense costs to obtain as incurred, expected period of benefie, amortization period	1 year

Revenue Recognition - Additio_2

Revenue Recognition - Additional Information 1 (Detail)	Dec. 28, 2019
Maximum [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2019-12-28
Revenue From Contract With Customer [Line Items]
Revenue, remaining performance obligations for contract, initial term	1 year

Revenue Recognition - Summary o

Revenue Recognition - Summary of Disaggregated Net Sales (Detail) - USD ($) $ in Thousands	3 Months Ended												12 Months Ended
	Dec. 28, 2019	Sep. 28, 2019	Jun. 29, 2019	Mar. 30, 2019	Dec. 29, 2018	[1]	Sep. 29, 2018	[1]	Jun. 30, 2018	[1]	Mar. 31, 2018	[1]	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Disaggregation Of Revenue [Line Items]
Net Sales	$ 239,567	$ 253,796	$ 254,175	$ 243,791	$ 260,341		$ 247,954		$ 238,147		$ 227,262		$ 991,329	$ 973,705	$ 903,221
U.S. Customers [Member]
Disaggregation Of Revenue [Line Items]
Net Sales													929,908	913,181	847,394
Non-U.S. Customers [Member]
Disaggregation Of Revenue [Line Items]
Net Sales													61,421	60,524	55,827
Powertrain [Member]
Disaggregation Of Revenue [Line Items]
Net Sales													395,975	393,979	374,372
Chassis [Member]
Disaggregation Of Revenue [Line Items]
Net Sales													297,350	278,584	238,239
Automotive Body [Member]
Disaggregation Of Revenue [Line Items]
Net Sales													251,506	256,344	245,869
Hardware [Member]
Disaggregation Of Revenue [Line Items]
Net Sales													$ 46,498	$ 44,798	$ 44,741
[1]	Quarterly information does not add to year to date information due to rounding

Capital Stock - Additional Info

Capital Stock - Additional Information (Detail) - USD ($)	1 Months Ended	12 Months Ended
	May 31, 2017	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016	Dec. 26, 2015	Dec. 27, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of outstanding shares owned by controlling family		18.00%
Shares authorized of undesignated capital stock for future issuance		50,000,000
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		1,034,023
Weighted-average grant-date fair value		$ 81.84	$ 73.84	$ 78.58
Compensation cost related to restricted stock		$ 2,100,000	$ 2,600,000	$ 2,800,000
Compensation cost related to stock options		700,000	500,000	300,000
Cash received from stock option exercises under the plan		123,000	201,000	31,000
Total 401(K) expense		$ 3,100,000	$ 4,300,000	$ 2,700,000
Common stock, shares held by 401(K) plan		218,728
Repurchase and cancellation of shares		22,380	26,280	19,110
Common stock repurchased, average price		$ 87.26	$ 74.79	$ 73.34
Common stock repurchased, value		$ 1,900,000	$ 2,000,000	$ 1,400,000
Share Repurchase Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock repurchased, average price		$ 78.84	$ 69.73	$ 74.26
Common stock repurchased, value		$ 39,400,000	$ 43,400,000	$ 74,700,000
Share repurchase program shares authorized to be repurchased						$ 400,000,000	$ 10,000,000
Share repurchase program shares authorized to be repurchased expiration date		Dec. 31, 2020
Shares repurchased under share repurchase program		499,564	622,223	1,006,365
Authorized date of repurchase of outstanding common stock		Dec. 12, 2013
Shares available for repurchase under share repurchase program		143,900,000
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		21,200	21,173	0
Compensation cost		$ 300,000	$ 400,000
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cash received from stock option exercises under the plan				$ 100,000
Performance Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant-date fair value		$ 81.44
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Capitalized compensation cost		$ 0	0	0
Unrecognized compensation cost related to non-vested stock options		$ 6,300,000
Unrecognized compensation cost related to nonvested stock options, weighted-average period		2 years 7 months 6 days
Tax benefit generated from compensation cost and credited		$ 200,000	100,000	$ 400,000
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant-date fair value		$ 24.32		$ 15.88	$ 15.81
Capitalized compensation cost		$ 0	0	$ 0
Unrecognized compensation cost related to non-vested stock options		$ 1,600,000
Unrecognized compensation cost related to nonvested stock options, weighted-average period		2 years 8 months 12 days
Tax benefit generated from compensation cost and credited		$ 0	$ 0	$ 600,000
Performance-Based Long Term Award Program [Member] | Executives [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term of compensation on compound annual growth in our pre-tax income		3 years

Capital Stock - Schedule of Wei

Capital Stock - Schedule of Weighted Average Valuation Assumptions Used to Calculate Fair Value of Stock Granted (Detail) - $ / shares	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Performance Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share price	$ 82.03
Expected dividend yield	0.00%
Expected stock price volatility	27.70%
Risk-free interest rate	2.50%
Expected life	2 years 9 months 18 days
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividend yield	0.00%	0.00%	0.00%
Expected stock price volatility	28.00%	27.00%	27.00%
Risk-free interest rate	2.30%	2.60%	1.50%
Expected life	5 years 4 months 24 days	3 years	3 years

Capital Stock - Summary of Rest

Capital Stock - Summary of Restricted Stock Activity (Detail) - $ / shares	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Beginning Balance, Shares	170,737	153,727	145,363
Granted, Shares	92,396	89,798	70,611
Vested, Shares	(41,586)	(45,707)	(56,953)
Cancelled, Shares	(44,056)	(27,081)	(5,294)
Ending Balance, Shares	177,491	170,737	153,727
Beginning Balance, Weighted Average Price	$ 63.94	$ 59.94	$ 49.22
Granted, Weighted Average Price	81.92	73.51	78.27
Vested, Weighted Average Price	55.72	62.56	56.03
Cancelled, Weighted Average Price	58.03	75.39	51.56
Ending Balance, Weighted Average Price	$ 76.70	$ 63.94	$ 59.94

Capital Stock - Summary of Stoc

Capital Stock - Summary of Stock Option Activity (Detail) - USD ($)	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Beginning Balance, Shares	188,469	122,547	101,084
Granted, Shares	44,025	81,995	58,024
Exercised, Shares	(38,009)	(15,113)	(32,751)
Cancelled, Shares	(12,773)	(960)	(3,810)
Ending Balance, Shares	181,712	188,469	122,547
Options Exercisable, Shares	63,432
Option Price per Share, Cancelled		$ 72.55
Options Exercisable, Option Price per Share	$ 62.39
Beginning Balance, Weighted Average Price	66.14	57.74	$ 29.52
Granted, Weighted Average Price	81.84	73.84	78.58
Exercised, Weighted Average Price	58.96	39.38	7.69
Cancelled, Weighted Average Price	75.52	72.55	56.72
Ending Balance, Weighted Average Price	$ 70.78	66.14	57.74
Ending Balance, Weighted Average Remaining Terms (years)	3 years 9 months 18 days
Options Exercisable, Weighted Average Remaining Terms (years)	2 years 3 months 18 days
Ending Balance, Aggregate Intrinsic Value	$ 1,308,808
Options Exercisable, Aggregate Intrinsic Value	$ 897,145
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Beginning Balance, Option Price per Share	$ 7.74	5.67	5.67
Option price per share, Granted	73.72	68.93	69.02
Option Price per Share, Exercised	7.74	5.67	6.90
Option Price per Share, Cancelled	41.59		41.59
Ending Balance, Option Price per Share	41.59	7.74	5.67
Options Exercisable, Option Price per Share	41.59
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Beginning Balance, Option Price per Share	82.94	82.59	53.32
Option price per share, Granted	84.93	82.94	82.59
Option Price per Share, Exercised	78.76	78.64	41.59
Option Price per Share, Cancelled	82.94		78.64
Ending Balance, Option Price per Share	84.93	$ 82.94	$ 82.59
Options Exercisable, Option Price per Share	$ 82.94

Capital Stock - Summary of Info

Capital Stock - Summary of Information Concerning Currently Outstanding and Exercisable Options (Detail)	12 Months Ended
	Dec. 28, 2019$ / sharesshares
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number Outstanding | shares	181,712
Weighted Average Remaining Contractual Life (Years)	3 years 9 months 18 days
Weighted Average Exercise Price	$ 70.78
Number Exercisable | shares	63,432
Options Exercisable, Weighted Average Exercise Price	$ 62.39
Range One [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Option Price per share, Minimum	41.59
Option Price per share, Maximum	$ 61.13
Number Outstanding | shares	38,848
Weighted Average Remaining Contractual Life (Years)	1 year 3 months 18 days
Weighted Average Exercise Price	$ 45.94
Number Exercisable | shares	29,136
Options Exercisable, Weighted Average Exercise Price	$ 45.94
Range Two [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Option Price per share, Minimum	61.14
Option Price per share, Maximum	$ 73.13
Number Outstanding | shares	52,413
Weighted Average Remaining Contractual Life (Years)	3 years 10 months 24 days
Weighted Average Exercise Price	$ 71.89
Number Exercisable | shares	13,762
Options Exercisable, Weighted Average Exercise Price	$ 71.68
Range Three [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Option Price per share, Minimum	73.14
Option Price per share, Maximum	$ 78.70
Number Outstanding | shares	24,654
Weighted Average Remaining Contractual Life (Years)	3 years 4 months 24 days
Weighted Average Exercise Price	$ 77.60
Number Exercisable | shares	9,650
Options Exercisable, Weighted Average Exercise Price	$ 78.64
Range Four [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Option Price per share, Minimum	78.71
Option Price per share, Maximum	$ 82.31
Number Outstanding | shares	35,803
Weighted Average Remaining Contractual Life (Years)	5 years 2 months 12 days
Weighted Average Exercise Price	$ 80.65
Number Exercisable | shares	6,871
Options Exercisable, Weighted Average Exercise Price	$ 78.76
Range Five [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Option Price per share, Minimum	82.32
Option Price per share, Maximum	$ 84.93
Number Outstanding | shares	29,994
Weighted Average Remaining Contractual Life (Years)	5 years 7 months 6 days
Weighted Average Exercise Price	$ 83.66
Number Exercisable | shares	4,013
Options Exercisable, Weighted Average Exercise Price	$ 82.83

Earnings Per Share - Additional

Earnings Per Share - Additional Information (Detail) - shares	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Earnings Per Share [Abstract]
Stock-based awards considered as anti-dilutive	92,000	116,000	106,000

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												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	$ 17,548	$ 21,308	$ 21,499	$ 23,407	$ 34,599		$ 34,017		$ 34,339		$ 30,647		$ 83,762	$ 133,602	$ 106,599
Denominator:
Weighted average basic shares outstanding													32,606	33,097	33,964
Effect of compensation awards													82	110	88
Weighted average diluted shares outstanding													32,688	33,207	34,052
Earnings Per Share:
Basic													$ 2.57	$ 4.04	$ 3.14
Diluted	$ 0.54	$ 0.65	$ 0.66	$ 0.71	$ 1.05	[1]	$ 1.03	[1]	$ 1.03	[1]	$ 0.93	[1]	$ 2.56	$ 4.02	$ 3.13
[1]	Quarterly information does not add to year to date information due to rounding

Business Segments - Additional

Business Segments - Additional Information (Detail) $ in Millions	12 Months Ended
	Dec. 28, 2019USD ($)CustomerSegment	Dec. 29, 2018USD ($)Customer	Dec. 30, 2017USD ($)Customer
Product Information [Line Items]
Number of reportable operating segment | Segment	1
Number of customers exceeding 10% of net sales | Customer	4	4	4
Net sales outside of the U.S. | $	$ 61.4	$ 60.5	$ 55.8
Sales Revenue, Net [Member] | Customer Concentration Risk [Member]
Product Information [Line Items]
Total percentage of sales to customers exceeding 10% of sales	66.00%	63.00%	61.00%

Quarterly Results of Operatio_3

Quarterly Results of Operations - Summary of Quarterly Results of Operations (Detail) - 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]
Net sales	$ 239,567	$ 253,796	$ 254,175	$ 243,791	$ 260,341	[1]	$ 247,954	[1]	$ 238,147	[1]	$ 227,262	[1]	$ 991,329	$ 973,705	$ 903,221
Income from operations	21,900	26,963	27,223	29,742	44,637	[1]	43,733	[1]	42,780	[1]	39,994	[1]	105,828	171,143	176,240
Net income	$ 17,548	$ 21,308	$ 21,499	$ 23,407	$ 34,599		$ 34,017		$ 34,339		$ 30,647		$ 83,762	$ 133,602	$ 106,599
Diluted earnings per share	$ 0.54	$ 0.65	$ 0.66	$ 0.71	$ 1.05	[1]	$ 1.03	[1]	$ 1.03	[1]	$ 0.93	[1]	$ 2.56	$ 4.02	$ 3.13
[1]	Quarterly information does not add to year to date information due to rounding

Subsequent Events - Additional

Subsequent Events - Additional Information (Detail) - Subsequent Events [Member] - USD ($)	Jan. 02, 2020	Jan. 01, 2020
Power Train Industries [Member]
Subsequent Event [Line Items]
Equity method investment, ownership percentage		40.00%
Power Train Industries [Member]
Subsequent Event [Line Items]
Business acquisition, percentage of outstanding stock acquired	60.00%
Business acquisition, total purchase price consideration	$ 18,200

Schedule II - Valuation and Qua

Schedule II - Valuation and Qualifying Accounts (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Allowance for Doubtful Accounts [Member]
Valuation and Qualifying Accounts
Balance, beginning of period	$ 982	$ 1,656	$ 1,345
Provision	39	(570)	299
Charge-offs	(64)	(151)	12
Acquisitions and other		47
Balance, end of period	957	982	1,656
Allowance for Customer Credits [Member]
Valuation and Qualifying Accounts
Balance, beginning of period	90,596	95,537	98,650
Provision	274,243	203,677	187,422
Charge-offs	(258,889)	(208,665)	(193,753)
Acquisitions and other		47	3,218
Balance, end of period	$ 105,950	$ 90,596	$ 95,537