Landstar System (LSTR) 10-Q 2 Nov 18 2018 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 29, 2018	Oct. 22, 2018
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 29, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q3
Trading Symbol	LSTR
Entity Registrant Name	LANDSTAR SYSTEM INC
Entity Central Index Key	853,816
Current Fiscal Year End Date	--12-29
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding		41,114,477

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 29, 2018	Dec. 30, 2017
Current Assets
Cash and cash equivalents	$ 213,974	$ 242,416
Short-term investments	40,203	48,928
Trade accounts receivable, less allowance of $6,173 and $6,131	702,183	631,164
Other receivables, including advances to independent contractors, less allowance of $6,188 and $6,012	18,586	24,301
Other current assets	24,191	14,394
Total current assets	999,137	961,203
Operating property, less accumulated depreciation and amortization of $241,321 and $218,700	268,011	276,011
Goodwill	38,560	39,065
Other assets	85,004	76,181
Total assets	1,390,712	1,352,460
Current Liabilities
Cash overdraft	39,759	42,242
Accounts payable	313,728	285,132
Current maturities of long-term debt	40,960	42,051
Insurance claims	43,268	38,919
Dividends payable		62,985
Accrued compensation	23,908	30,103
Other current liabilities	53,553	47,211
Total current liabilities	515,176	548,643
Long-term debt, excluding current maturities	72,887	83,062
Insurance claims	30,775	30,141
Deferred income taxes and other noncurrent liabilities	45,664	36,737
Equity
Landstar System, Inc. and subsidiary shareholders' equity Common stock, $0.01 par value, authorized 160,000,000 shares, issued 67,869,378 and 67,740,380 shares	679	677
Additional paid-in capital	221,563	209,599
Retained earnings	1,779,680	1,611,158
Cost of 26,755,001 and 25,749,493 shares of common stock in treasury	(1,273,512)	(1,167,600)
Accumulated other comprehensive loss	(4,569)	(3,162)
Total Landstar System, Inc. and subsidiary shareholders' equity	723,841	650,672
Noncontrolling interest	2,369	3,205
Total equity	726,210	653,877
Total liabilities and equity	$ 1,390,712	$ 1,352,460

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 29, 2018	Dec. 30, 2017
Allowance on trade accounts receivable	$ 6,173	$ 6,131
Allowance on other receivables	6,188	6,012
Accumulated depreciation and amortization on operating property	$ 241,321	$ 218,700
Common stock, par value	$ 0.01	$ 0.01
Common stock, authorized shares	160,000,000	160,000,000
Common stock, issued shares	67,869,378	67,740,380
Treasury stock, shares	26,755,001	25,749,493

Consolidated Statements of Inco

Consolidated Statements of Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2018	Sep. 30, 2017	Sep. 29, 2018	Sep. 30, 2017
Revenue	$ 1,202,081	$ 943,430	$ 3,432,793	$ 2,594,772
Investment income	1,002	711	2,754	1,733
Costs and expenses:
Purchased transportation	931,473	726,827	2,658,710	1,989,938
Commissions to agents	99,304	76,598	275,828	210,678
Other operating costs, net of gains on asset sales/dispositions	8,966	8,097	24,176	22,497
Insurance and claims	18,819	17,927	57,718	46,333
Selling, general and administrative	46,699	43,995	140,948	123,179
Depreciation and amortization	10,754	10,130	32,520	29,961
Total costs and expenses	1,116,015	883,574	3,189,900	2,422,586
Operating income	87,068	60,567	245,647	173,919
Interest and debt expense	816	657	2,455	2,559
Income before income taxes	86,252	59,910	243,192	171,360
Income taxes	19,304	17,490	56,279	59,047
Net income	66,948	42,420	186,913	112,313
Less: Net loss attributable to noncontrolling interest	(37)	(23)	(112)	(23)
Net income attributable to Landstar System, Inc. and subsidiary	$ 66,985	$ 42,443	$ 187,025	$ 112,336
Earnings per common share attributable to Landstar System, Inc. and subsidiary	$ 1.63	$ 1.01	$ 4.50	$ 2.68
Diluted earnings per share attributable to Landstar System, Inc. and subsidiary	$ 1.63	$ 1.01	$ 4.50	$ 2.67
Average number of shares outstanding:
Earnings per common share	41,101,000	41,957,000	41,530,000	41,924,000
Diluted earnings per share	41,137,000	42,028,000	41,576,000	42,013,000
Dividends per common share	$ 0.165	$ 0.100	$ 0.465	$ 0.280

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2018	Sep. 30, 2017	Sep. 29, 2018	Sep. 30, 2017
Net income attributable to Landstar System, Inc. and subsidiary	$ 66,985	$ 42,443	$ 187,025	$ 112,336
Other comprehensive (loss) income:
Unrealized holding (losses) gains on available-for-sale investments, net of tax (benefit) expense of ($231), $136, $2 and $47	7	86	(876)	251
Foreign currency translation (losses) gains	708	545	(531)	1,130
Other comprehensive (loss) income	715	631	(1,407)	1,381
Comprehensive income attributable to Landstar System, Inc. and subsidiary	$ 67,700	$ 43,074	$ 185,618	$ 113,717

Consolidated Statements of Co_2

Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2018	Sep. 30, 2017	Sep. 29, 2018	Sep. 30, 2017
Unrealized holding (losses) gains on available-for-sale investments, tax (benefit) expense	$ 2	$ 47	$ (231)	$ 136

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 29, 2018	Sep. 30, 2017
OPERATING ACTIVITIES
Net income	$ 186,913	$ 112,313
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization of operating property and intangible assets	32,520	29,961
Non-cash interest charges	190	189
Provisions for losses on trade and other accounts receivable	5,360	5,643
Gains on sales/disposals of operating property	(1,025)	(900)
Deferred income taxes, net	7,459	(708)
Stock-based compensation	13,003	3,660
Changes in operating assets and liabilities:
Increase in trade and other accounts receivable	(60,785)	(89,504)
Increase in other assets	(9,779)	(8,671)
Increase in accounts payable	22,121	53,290
Increase in other liabilities	3,245	12,980
Increase in insurance claims	4,983	14,011
NET CASH PROVIDED BY OPERATING ACTIVITIES	204,205	132,264
INVESTING ACTIVITIES
Sales and maturities of investments	34,259	42,917
Purchases of investments	(36,296)	(44,423)
Purchases of operating property	(7,325)	(8,800)
Proceeds from sales of operating property	3,542	3,594
Consideration paid for acquisitions		(8,199)
NET CASH USED BY INVESTING ACTIVITIES	(5,820)	(14,911)
FINANCING ACTIVITIES
Decrease in cash overdraft	(2,483)	(2,398)
Dividends paid	(82,261)	(11,739)
Proceeds from exercises of stock options	1,397	2,531
Taxes paid in lieu of shares issued related to stock-based compensation plans	(3,936)	(371)
Purchases of common stock	(105,488)
Principal payments on capital lease obligations	(32,663)	(35,662)
Payment of contingent consideration	(985)
NET CASH USED BY FINANCING ACTIVITIES	(226,419)	(47,639)
Effect of exchange rate changes on cash and cash equivalents	(408)	1,130
(Decrease) increase in cash and cash equivalents	(28,442)	70,844
Cash and cash equivalents at beginning of period	242,416	178,897
Cash and cash equivalents at end of period	$ 213,974	$ 249,741

Consolidated Statement of Chang

Consolidated Statement of Changes in Equity - 9 months ended Sep. 29, 2018 - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Retained Earnings	Treasury Stock at Cost	Accumulated Other Comprehensive (Loss) Income	Non-controlling Interests
Beginning Balance (in shares) at Dec. 30, 2017		67,740,380			25,749,493
Beginning Balance at Dec. 30, 2017	$ 653,877	$ 677	$ 209,599	$ 1,611,158	$ (1,167,600)	$ (3,162)	$ 3,205
Net income (loss)	186,913			187,025			(112)
Dividends	(19,276)			(19,276)
Purchases of common stock (in shares)					1,000,000
Purchases of common stock	(105,488)				$ (105,488)
Transaction with noncontrolling interests			1,078				(1,078)
Issuance of stock related to stock-based compensation plans (in shares)		128,998			5,508
Issuance of stock related to stock-based compensation plans	(2,539)	$ 2	(2,117)		$ (424)
Stock-based compensation	13,003		13,003
Other comprehensive (loss) income	(1,053)					(1,407)	354
Ending Balance (in shares) at Sep. 29, 2018		67,869,378			26,755,001
Ending Balance at Sep. 29, 2018	726,210	$ 679	$ 221,563	1,779,680	$ (1,273,512)	$ (4,569)	$ 2,369
Adoption of accounting standards (Note 12) | Accounting Standards Update 2014-09	$ 773			$ 773

Consolidated Statement of Cha_2

Consolidated Statement of Changes in Equity (Parenthetical) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 29, 2018	Sep. 30, 2017	Sep. 29, 2018	Sep. 30, 2017
Dividends per common share	$ 0.165	$ 0.100	$ 0.465	$ 0.280

Business Description

Business Description	9 Months Ended
	Sep. 29, 2018
Business Description	The consolidated financial statements include the accounts of Landstar System, Inc. and its subsidiary, Landstar System Holdings, Inc., and reflect all adjustments (all of a normal, recurring nature) which are, in the opinion of management, necessary for a fair statement of the results for the periods presented. The preparation of the consolidated financial statements requires the use of management’s estimates. Actual results could differ from those estimates. Landstar System, Inc. and its subsidiary are herein referred to as “Landstar” or the “Company.” Significant intercompany accounts have been eliminated in consolidation. Landstar owns, through various subsidiaries, a controlling interest in Landstar Metro, S.A.P.I. de C.V., a transportation logistics company (“Landstar Metro”), and Landstar Metro Servicios S.A.P.I. de C.V., a services company (“Landstar Servicios”), each based in Mexico City, Mexico. Given Landstar’s controlling interest in each of Landstar Metro and Landstar Servicios, the accounts of Landstar Metro and Landstar Servicios have been consolidated herein and a noncontrolling interest has been recorded for the noncontrolling investors’ interests in the net assets and operations of Landstar Metro and Landstar Servicios. In May 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update 2014-09— Revenue from Contracts with Customers 2014-09”). 2014-09 10-K

Significant Accounting Policies

Significant Accounting Policies	9 Months Ended
	Sep. 29, 2018
Significant Accounting Policies	(1) Significant Accounting Policies Revenue Recognition The nature of the Company’s freight transportation services and its performance obligations to customers, regardless of the mode of transportation used to perform such services, relate to the safe and on-time pick-up shipment-by-shipment shipment-by-shipment pre-defined (30-60) pick-up pick-up

Acquired Business and Noncontro

Acquired Business and Noncontrolling Interests	9 Months Ended
	Sep. 29, 2018
Acquired Business and Noncontrolling Interests	(2) Acquired Business and Noncontrolling Interests During 2017, the Company incorporated each of Landstar Metro and Landstar Servicios. On September 20, 2017, Landstar Metro acquired substantially all of the assets of the asset-light transportation logistics business of Fletes Avella, S.A. de C.V., a Mexican transportation logistics company (the “Mexican Asset Acquisition”). At December 30, 2017, there was approximately $1,900,000 in liabilities outstanding consisting of additional contingent purchase price and associated indirect taxes. In connection with the Mexican Asset Acquisition, individuals affiliated with the seller subscribed in the aggregate for equity interests in Landstar Metro and Landstar Servicios and, as of September 29, 2018, own in the aggregate approximately 21% of the equity interests of each of them. The Mexican Asset Acquisition was accounted for as a business combination in accordance with Accounting Standards Codification 805, Business Combinations As it relates to the noncontrolling interests of Landstar Metro and Landstar Servicios, the Company has the option to purchase, and the minority equityholders have the option to sell, during the period commencing on the third anniversary of September 20, 2017, the closing date of the subscription by the minority equityholders (the “Closing Date”), and at any time after the fourth anniversary of the Closing Date, at fair value all but not less than all of the noncontrolling interests in Landstar Metro and Landstar Servicios. The noncontrolling interests are also subject to customary restrictions on transfer, including a right of first refusal in favor of the Company.

Share-based Payment Arrangement

Share-based Payment Arrangements	9 Months Ended
	Sep. 29, 2018
Share-based Payment Arrangements	(3) Share-based Payment Arrangements As of September 29, 2018, the Company had two employee equity incentive plans, the 2002 employee stock option and stock incentive plan (the “ESOSIP”) and the 2011 equity incentive plan (the “2011 EIP”). No further grants can be made under the ESOSIP. The Company also has a stock compensation plan for members of its Board of Directors, the Amended and Restated 2013 Directors Stock Compensation Plan (as amended and restated as of May 17, 2016, the “2013 DSCP”). 6,000,000 shares of the Company’s common stock were authorized for issuance under the 2011 EIP and 115,000 shares of the Company’s common stock were authorized for issuance under the 2013 DSCP. The ESOSIP, 2011 EIP and 2013 DSCP are each referred to herein as a “Plan,” and, collectively, as the “Plans.” Amounts recognized in the financial statements with respect to these Plans are as follows (in thousands): Thirty Nine Weeks Ended Thirteen Weeks Ended September 29, 2018 September 30, 2017 September 29, 2018 September 30, 2017 Total cost of the Plans during the period $ 13,003 $ 3,660 $ 4,901 $ 1,423 Amount of related income tax benefit recognized during the period (5,305 ) (2,492 ) (1,837 ) (678 ) Net cost of the Plans during the period $ 7,698 $ 1,168 $ 3,064 $ 745 Included in income tax benefits recognized in the thirty-nine-week periods ended September 29, 2018 and September 30, 2017 were income tax benefits of $80,000 and $310,000, respectively, recognized on disqualifying dispositions of the Company’s common stock by employees who obtained shares of common stock through exercises of incentive stock options. Also included in income tax benefits recognized in the thirty-nine-week periods ended September 29, 2018 and September 30, 2017 were excess tax benefits from stock-based awards of $2,046,000 and $868,000, respectively. As of September 29, 2018, there were 72,742 shares of the Company’s common stock reserved for issuance under the 2013 DSCP and 4,439,761 shares of the Company’s common stock reserved for issuance in the aggregate under the ESOSIP and 2011 EIP. Restricted Stock Units The following table summarizes information regarding the Company’s outstanding restricted stock unit (“RSU”) awards with either a performance condition or a market condition under the Plans: Number Weighted Average Grant Date Fair Value Outstanding at December 30, 2017 387,372 $ 55.75 Granted 65,494 $ 96.08 Vested (67,971 ) $ 53.92 Forfeited (92,880 ) $ 52.36 Outstanding at September 29, 2018 292,015 $ 66.30 During the thirty-nine-week period ended September 29, 2018, the Company granted RSUs with a performance condition and RSUs with a market condition, as further described below. Outstanding RSUs at both December 30, 2017 and September 29, 2018 include RSUs with a performance condition and RSUs with a market condition, as further described in the Company’s 2017 Annual Report on Form 10-K. RSUs with a performance condition granted on February 2, 2018 may vest on January 31 of 2021, 2022 and 2023 based on growth in operating income and pre-tax On April 24, 2018, the Company granted 9,324 RSUs that vest based on a market condition. These RSUs may vest on June 30 of 2022, 2023 and 2024 based on the Company’s total shareholder return (“TSR”) compound annual growth rate over the vesting periods, adjusted to reflect dividends (if any) paid during such periods and capital adjustments as may be necessary. The maximum number of common shares available for issuance under the April 24, 2018 grant equals 150% of the number of RSUs granted. The fair value of this RSU award was determined at the time of grant based on the expected achievement of the market condition at the end of each vesting period. With respect to these RSU awards, the Company reports compensation expense ratably over the life of the award based on an estimated number of units that will vest over the life of the award, multiplied by the fair value of the RSU. Previously recognized compensation cost would be reversed only if the employee terminated employment prior to completing the requisite service period. The Company recognized approximately $11,303,000 and $2,254,000 of share-based compensation expense related to RSU awards in the thirty-nine-week periods ended September 29, 2018 and September 30, 2017, respectively. As of September 29, 2018, there was a maximum of $23.1 million of total unrecognized compensation cost related to RSU awards granted under the Plans with an expected average remaining life of approximately 3.3 years. With respect to RSU awards with a performance condition, the amount of future compensation expense to be recognized will be determined based on future operating results. Stock Options The following table summarizes information regarding the Company’s outstanding stock options under the Plans: Number of Weighted Average per Share Weighted Average Term (years) Aggregate Intrinsic Options outstanding at December 30, 2017 189,040 $ 49.34 Exercised (97,676 ) $ 48.38 Options outstanding at September 29, 2018 91,364 $ 50.36 3.3 $ 6,546 Options exercisable at September 29, 2018 90,364 $ 50.27 3.3 $ 6,482 The total intrinsic value of stock options exercised during the thirty-nine-week periods ended September 29, 2018 and September 30, 2017 was $6,584,000 and $5,303,000, respectively. As of September 29, 2018, there was no unrecognized compensation cost related to non-vested Non-vested The following table summarizes information regarding the Company’s outstanding shares of non-vested Number of Shares and Deferred Stock Weighted Average Grant Date Fair Value Non-vested 54,755 $ 78.02 Granted 22,803 $ 113.35 Vested (19,814 ) $ 75.11 Forfeited (1,757 ) $ 71.12 Non-vested 55,987 $ 93.66 The fair value of each share of non-vested non-vested As of September 29, 2018, there was $3,756,000 of total unrecognized compensation cost related to non-vested non-vested

Income Taxes

Income Taxes	9 Months Ended
	Sep. 29, 2018
Income Taxes	(4) Income Taxes The Tax Cuts and Jobs Act (the “Tax Reform Act”) permanently reduced the U.S. corporate income tax rate from a maximum of 35% to a flat 21% rate, effective January 1, 2018. The provisions for income taxes for the 2018 and 2017 thirty-nine-week periods were based on estimated annual effective income tax rates of 24.5% and 37.8%, respectively, adjusted for discrete events, such as benefits resulting from stock-based awards. The applicable effective income tax rates for the 2018 and 2017 thirty-nine-week periods were 23.1% and 34.5%, respectively. The effective income tax rate for the 2018 thirty-nine week period was higher than the statutory federal income tax rate primarily as a result of state taxes, the elimination of the performance-based compensation exception under Section 162(m) included in the Tax Reform Act and the meals and entertainment exclusion, partially offset by excess tax benefits realized on stock based awards and favorable adjustments recognized during the 2018 period relating to federal domestic production activities deductions and research and development credits during the thirteen-week period ended September 29, 2018. The effective income tax rate for the 2017 thirty-nine week period was lower than the statutory federal income tax rate primarily as a result of federal domestic production activities deductions and research and development credits recognized as discrete items during the thirteen-week period ended September 30, 2017, partially offset by the effect of state taxes and the meals and entertainment exclusion.

Earnings Per Share

Earnings Per Share	9 Months Ended
	Sep. 29, 2018
Earnings Per Share	(5) Earnings Per Share Earnings per common share attributable to Landstar System, Inc. and subsidiary are based on the weighted average number of shares outstanding, including outstanding non-vested The following table provides a reconciliation of the average number of common shares outstanding used to calculate earnings per common share attributable to Landstar System, Inc. and subsidiary to the average number of common shares and common share equivalents outstanding used to calculate diluted earnings per share attributable to Landstar System, Inc. and subsidiary (in thousands): Thirty Nine Weeks Ended Thirteen Weeks Ended September 29, 2018 September 30, 2017 September 29, 2018 September 30, 2017 Average number of common shares outstanding 41,530 41,924 41,101 41,957 Incremental shares from assumed exercises of stock options 46 89 36 71 Average number of common shares and common share equivalents outstanding 41,576 42,013 41,137 42,028 For both of the thirty-nine-week periods ended September 29, 2018 and September 30, 2017, no options outstanding to purchase shares of common stock were antidilutive. Outstanding RSUs were excluded from the calculation of diluted earnings per share attributable to Landstar System, Inc. and subsidiary for all periods because the performance metric requirements or market condition for vesting had not been satisfied.

Additional Cash Flow Informatio

Additional Cash Flow Information	9 Months Ended
	Sep. 29, 2018
Additional Cash Flow Information	(6) Additional Cash Flow Information During the 2018 thirty-nine-week period, Landstar paid income taxes and interest of $56,083,000 and $2,737,000, respectively. During the 2017 thirty-nine-week period, Landstar paid income taxes and interest of $65,688,000 and $2,981,000, respectively. Landstar acquired operating property by entering into capital leases in the amounts of $21,397,000 and $14,760,000 in the 2018 or 2017 thirty-nine-week periods. During the 2018 thirty-nine-week period, Landstar paid $2,162,000 relating to the completion of its freight staging and transload facility in Laredo, Texas, for which the Company accrued a corresponding liability included in accounts payable at December 30, 2017. Capital expenditure purchases are recorded as cash outflows from investing activities in the consolidated statement of cash flows in the period in which they are paid.

Segment Information

Segment Information	9 Months Ended
	Sep. 29, 2018
Segment Information	(7) Segment Information The following table summarizes information about the Company’s reportable business segments as of and for the thirty-nine-week and thirteen-week periods ended September 29, 2018 and September 30, 2017 (in thousands): Thirty Nine Weeks Ended September 29, 2018 September 30, 2017 Transportation Logistics Insurance Total Transportation Logistics Insurance Total External revenue $ 3,394,298 $ 38,495 $ 3,432,793 $ 2,559,847 $ 34,925 $ 2,594,772 Internal revenue 30,413 30,413 29,773 29,773 Investment income 2,754 2,754 1,733 1,733 Operating income 227,176 18,471 245,647 148,693 25,226 173,919 Expenditures on long-lived assets 7,325 7,325 8,800 8,800 Goodwill 38,560 38,560 39,914 39,914 Thirteen Weeks Ended September 29, 2018 September 30, 2017 Transportation Logistics Insurance Total Transportation Logistics Insurance Total External revenue $ 1,188,737 $ 13,344 $ 1,202,081 $ 931,692 $ 11,738 $ 943,430 Internal revenue 7,496 7,496 7,335 7,335 Investment income 1,002 1,002 711 711 Operating income 80,878 6,190 87,068 54,181 6,386 60,567 Expenditures on long-lived assets 3,204 3,204 2,172 2,172 In the thirty-nine-week and thirteen-week periods ended September 29, 2018 and September 30, 2017, no single customer accounted for more than 10% of the Company’s consolidated revenue.

Other Comprehensive Income

Other Comprehensive Income	9 Months Ended
	Sep. 29, 2018
Other Comprehensive Income	(8) Other Comprehensive Income The following table presents the components of and changes in accumulated other comprehensive income attributable to Landstar System, Inc. and subsidiary, net of related income taxes, as of and for the thirty-nine-week period ended September 29, 2018 (in thousands): Unrealized Available-for-Sale Foreign Currency Total Balance as of December 30, 2017 $ (144 ) $ (3,018 ) $ (3,162 ) Other comprehensive loss (876 ) (531 ) (1,407 ) Balance as of September 29, 2018 $ (1,020 ) $ (3,549 ) $ (4,569 ) Amounts reclassified from accumulated other comprehensive income to investment income due to the realization of previously unrealized gains and losses in the accompanying consolidated statements of income were not significant for the thirty-nine-week period ended September 29, 2018.

Investments

Investments	9 Months Ended
	Sep. 29, 2018
Investments	(9) Investments Investments include primarily investment-grade corporate bonds having maturities of up to five years (the “bond portfolio”) and money market investments. Investments in the bond portfolio are reported as available-for-sale available-for-sale non-transferability, The amortized cost and fair values of available-for-sale Amortized Gross Gross Fair Value September 29, 2018 Money market investments $ 12,430 $ — $ — $ 12,430 Asset-backed securities 728 — 5 723 Corporate bonds and direct obligations of government agencies 99,833 15 1,309 98,539 Total $ 112,991 $ 15 $ 1,314 $ 111,692 December 30, 2017 Money market investments $ 27,895 $ — $ — $ 27,895 Asset-backed securities 2,805 — 5 2,800 Corporate bonds and direct obligations of government agencies 80,442 117 335 80,224 Total $ 111,142 $ 117 $ 340 $ 110,919 For those available-for-sale Less than 12 months 12 months or longer Total Fair Value Unrealized Loss Fair Value Unrealized Loss Fair Value Unrealized Loss September 29, 2018 Asset-backed securities $ 300 $ 2 $ 423 $ 3 $ 723 $ 5 Corporate bonds and direct obligations of government agencies 73,890 831 20,368 478 94,258 1,309 Total $ 74,190 $ 833 $ 20,791 $ 481 $ 94,981 $ 1,314 December 30, 2017 Asset-backed securities $ 1,864 $ 4 $ 632 $ 1 $ 2,496 $ 5 Corporate bonds and direct obligations of government agencies 41,322 220 14,016 115 55,338 335 Total $ 43,186 $ 224 $ 14,648 $ 116 $ 57,834 $ 340 The Company believes unrealized losses on investments were primarily caused by rising interest rates rather than changes in credit quality. The Company expects to recover the amortized cost basis of these securities as it does not intend to sell, and does not anticipate being required to sell, these securities before recovery of the cost basis. For these reasons, the Company does not consider the unrealized losses on these securities to be other-than-temporary at September 29, 2018.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 29, 2018
Commitments and Contingencies	(10) Commitments and Contingencies Short-term investments include $40,203,000 in current maturities of investments held by the Company’s insurance segment at September 29, 2018. The non-current non-current During 2017, the Company incorporated each of Landstar Metro and Landstar Servicios. On September 20, 2017, Landstar Metro acquired substantially all of the assets of the asset-light transportation logistics business of Fletes Avella, S.A. de C.V., a Mexican transportation logistics company. In connection with the Mexican Asset Acquisition, individuals affiliated with the seller subscribed in the aggregate for equity interests in Landstar Metro and Landstar Servicios and, as of September 29, 2018, own in the aggregate approximately 21% of the equity interests of each of them. As it relates to the noncontrolling interests of Landstar Metro and Landstar Servicios, the Company has the option to purchase, and the minority equityholders have the option to sell, during the period commencing on the third anniversary of September 20, 2017, the closing date of the subscription by the minority equityholders (the “Closing Date”), and at any time after the fourth anniversary of the Closing Date, at fair value all but not less than all of the noncontrolling interests in Landstar Metro and Landstar Servicios. The noncontrolling interests are also subject to customary restrictions on transfer, including a right of first refusal in favor of the Company. The Company is involved in certain claims and pending litigation arising from the normal conduct of business. Many of these claims are covered in whole or in part by insurance. Based on knowledge of the facts and, in certain cases, opinions of outside counsel, management believes that adequate provisions have been made for probable losses with respect to the resolution of all such claims and pending litigation and that the ultimate outcome, after provisions therefor, will not have a material adverse effect on the financial condition of the Company, but could have a material effect on the results of operations in a given quarter or year.

Change in Accounting Estimate f

Change in Accounting Estimate for Self-Insured Claims	9 Months Ended
	Sep. 29, 2018
Change in Accounting Estimate for Self-Insured Claims	(11) Change in Accounting Estimate for Self-Insured Claims Landstar provides for the estimated costs of self-insured claims primarily on an actuarial basis. The amount recorded for the estimated liability for claims incurred is based upon the facts and circumstances known on the applicable balance sheet date. The ultimate resolution of these claims may be for an amount greater or less than the amount estimated by management. The Company continually revises its existing claim estimates as new or revised information becomes available on the status of each claim. Historically, the Company has experienced both favorable and unfavorable development of prior years’ claims estimates. The following table summarizes the effect of the increase in the cost of insurance claims resulting from unfavorable development of prior year self-insured claims estimates on operating income, net income attributable to Landstar System, Inc. and subsidiary and earnings per share attributable to Landstar System, Inc. and subsidiary amounts in the consolidated statements of income for the thirty-nine-week and thirteen-week periods ended September 29, 2018 and September 30, 2017 (in thousands, except per share amounts): Thirty Nine Weeks Ended Thirteen Weeks Ended September 29, 2018 September 30, 2017 September 29, 2018 September 30, 2017 Operating income $ 11,596 $ 1,327 $ 3,352 $ 1,124 Net income attributable to Landstar System, Inc. and subsidiary 8,755 825 2,531 699 Earnings per share attributable to Landstar System, Inc. and subsidiary $ 0.21 $ 0.02 $ 0.06 $ 0.02 Diluted earnings per share attributable to Landstar System, Inc. and subsidiary $ 0.21 $ 0.02 $ 0.06 $ 0.02 The unfavorable development of prior years’ claims in the thirty-nine-week period ended September 29, 2018 was primarily attributable to five claims.

Recent Accounting Pronouncement

Recent Accounting Pronouncements	9 Months Ended
	Sep. 29, 2018
Recent Accounting Pronouncements	(12) Recent Accounting Pronouncements Adoption of New Accounting Standards In May 2014, the FASB issued ASU 2014-09. 2014-09 2014-09 2014-09 The cumulative effect of the changes made to our consolidated December 31, 2017 balance sheet for the adoption of ASU 2014-09 Balance at December 30, 2017 Adjustments Due to ASU 2014-09 Balance at December 31, 2017 Balance Sheet Assets Trade accounts receivable, net $ 631,164 $ 9,879 $ 641,043 Other current assets 14,394 (469 ) 13,925 Liabilities Accounts payable 285,132 8,637 293,769 Equity Retained earnings 1,611,158 773 1,611,931 In accordance with the new revenue standard requirements, the impact of adoption on our consolidated income statement and balance sheet was as follows (in thousands): For the Thirty Nine Weeks ended September 29, 2018 As Reported Balances Without 2014-09 Effect of Change Income statement Revenues Transportation $ 3,394,298 $ 3,390,242 $ 4,056 Insurance 38,495 38,495 — Costs and expenses Purchased transportation 2,658,710 2,655,491 3,219 Commissions to agents 275,828 275,538 290 Income taxes 56,279 56,145 134 Net income attributable to Landstar System, Inc. and subsidiary 187,025 186,612 413 September 29, 2018 As Reported Balances Without 2014-09 Effect of Change Balance Sheet Assets Trade accounts receivable, net $ 702,183 $ 688,248 $ 13,935 Other current assets 24,191 24,794 (603 ) Liabilities Accounts payable 313,728 301,582 12,146 Equity Retained earnings 1,779,680 1,778,494 1,186 Accounting Standards Issued But Not Yet Adopted In February 2016, the FASB issued Accounting Standards Update 2016-02 Leases 2016-02”). 2016-02 right-of-use 2016-02 2016-02 In June 2016, the FASB issued Accounting Standards Update 2016-13– Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments 2016-13”), 2016-13 2016-13

Significant Accounting Polici_2

Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 29, 2018
Revenue Recognition	Revenue Recognition The nature of the Company’s freight transportation services and its performance obligations to customers, regardless of the mode of transportation used to perform such services, relate to the safe and on-time pick-up shipment-by-shipment shipment-by-shipment pre-defined (30-60) pick-up pick-up

Share-based Payment Arrangeme_2

Share-based Payment Arrangements (Tables)	9 Months Ended
	Sep. 29, 2018
Amounts Recognized in Financial Statements with Respect to Plans	Amounts recognized in the financial statements with respect to these Plans are as follows (in thousands): Thirty Nine Weeks Ended Thirteen Weeks Ended September 29, 2018 September 30, 2017 September 29, 2018 September 30, 2017 Total cost of the Plans during the period $ 13,003 $ 3,660 $ 4,901 $ 1,423 Amount of related income tax benefit recognized during the period (5,305 ) (2,492 ) (1,837 ) (678 ) Net cost of the Plans during the period $ 7,698 $ 1,168 $ 3,064 $ 745
Summary of Information Regarding Stock Options	The following table summarizes information regarding the Company’s outstanding stock options under the Plans: Number of Weighted Average per Share Weighted Average Term (years) Aggregate Intrinsic Options outstanding at December 30, 2017 189,040 $ 49.34 Exercised (97,676 ) $ 48.38 Options outstanding at September 29, 2018 91,364 $ 50.36 3.3 $ 6,546 Options exercisable at September 29, 2018 90,364 $ 50.27 3.3 $ 6,482
Restricted Stock Units (RSUs)
Schedule of Information on Restricted Stock Units	The following table summarizes information regarding the Company’s outstanding restricted stock unit (“RSU”) awards with either a performance condition or a market condition under the Plans: Number Weighted Average Grant Date Fair Value Outstanding at December 30, 2017 387,372 $ 55.75 Granted 65,494 $ 96.08 Vested (67,971 ) $ 53.92 Forfeited (92,880 ) $ 52.36 Outstanding at September 29, 2018 292,015 $ 66.30
Non Vested Restricted Stock and Deferred Stock Units
Schedule of Information on Non-Vested Restricted Stock and Deferred Stock Units	The following table summarizes information regarding the Company’s outstanding shares of non-vested Number of Shares and Deferred Stock Weighted Average Grant Date Fair Value Non-vested 54,755 $ 78.02 Granted 22,803 $ 113.35 Vested (19,814 ) $ 75.11 Forfeited (1,757 ) $ 71.12 Non-vested 55,987 $ 93.66

Earnings Per Share (Tables)

Earnings Per Share (Tables)	9 Months Ended
	Sep. 29, 2018
Reconciliation of Average Number of Common Shares Outstanding to Average Number of Diluted Shares Outstanding	The following table provides a reconciliation of the average number of common shares outstanding used to calculate earnings per common share attributable to Landstar System, Inc. and subsidiary to the average number of common shares and common share equivalents outstanding used to calculate diluted earnings per share attributable to Landstar System, Inc. and subsidiary (in thousands): Thirty Nine Weeks Ended Thirteen Weeks Ended September 29, 2018 September 30, 2017 September 29, 2018 September 30, 2017 Average number of common shares outstanding 41,530 41,924 41,101 41,957 Incremental shares from assumed exercises of stock options 46 89 36 71 Average number of common shares and common share equivalents outstanding 41,576 42,013 41,137 42,028

Segment Information (Tables)

Segment Information (Tables)	9 Months Ended
	Sep. 29, 2018
Information Regarding Reportable Business Segments	The following table summarizes information about the Company’s reportable business segments as of and for the thirty-nine-week and thirteen-week periods ended September 29, 2018 and September 30, 2017 (in thousands): Thirty Nine Weeks Ended September 29, 2018 September 30, 2017 Transportation Logistics Insurance Total Transportation Logistics Insurance Total External revenue $ 3,394,298 $ 38,495 $ 3,432,793 $ 2,559,847 $ 34,925 $ 2,594,772 Internal revenue 30,413 30,413 29,773 29,773 Investment income 2,754 2,754 1,733 1,733 Operating income 227,176 18,471 245,647 148,693 25,226 173,919 Expenditures on long-lived assets 7,325 7,325 8,800 8,800 Goodwill 38,560 38,560 39,914 39,914 Thirteen Weeks Ended September 29, 2018 September 30, 2017 Transportation Logistics Insurance Total Transportation Logistics Insurance Total External revenue $ 1,188,737 $ 13,344 $ 1,202,081 $ 931,692 $ 11,738 $ 943,430 Internal revenue 7,496 7,496 7,335 7,335 Investment income 1,002 1,002 711 711 Operating income 80,878 6,190 87,068 54,181 6,386 60,567 Expenditures on long-lived assets 3,204 3,204 2,172 2,172

Other Comprehensive Income (Tab

Other Comprehensive Income (Tables)	9 Months Ended
	Sep. 29, 2018
Components of and Changes in Accumulated Other Comprehensive Income, Net of Related Income Taxes	The following table presents the components of and changes in accumulated other comprehensive income attributable to Landstar System, Inc. and subsidiary, net of related income taxes, as of and for the thirty-nine-week period ended September 29, 2018 (in thousands): Unrealized Available-for-Sale Foreign Currency Total Balance as of December 30, 2017 $ (144 ) $ (3,018 ) $ (3,162 ) Other comprehensive loss (876 ) (531 ) (1,407 ) Balance as of September 29, 2018 $ (1,020 ) $ (3,549 ) $ (4,569 )

Investments (Tables)

Investments (Tables)	9 Months Ended
	Sep. 29, 2018
Amortized Cost and Fair Value of Available-for-Sale Investments	The amortized cost and fair values of available-for-sale Amortized Gross Gross Fair Value September 29, 2018 Money market investments $ 12,430 $ — $ — $ 12,430 Asset-backed securities 728 — 5 723 Corporate bonds and direct obligations of government agencies 99,833 15 1,309 98,539 Total $ 112,991 $ 15 $ 1,314 $ 111,692 December 30, 2017 Money market investments $ 27,895 $ — $ — $ 27,895 Asset-backed securities 2,805 — 5 2,800 Corporate bonds and direct obligations of government agencies 80,442 117 335 80,224 Total $ 111,142 $ 117 $ 340 $ 110,919
Schedule of Unrealized Loss on Available-for-Sale Investments	For those available-for-sale Less than 12 months 12 months or longer Total Fair Value Unrealized Loss Fair Value Unrealized Loss Fair Value Unrealized Loss September 29, 2018 Asset-backed securities $ 300 $ 2 $ 423 $ 3 $ 723 $ 5 Corporate bonds and direct obligations of government agencies 73,890 831 20,368 478 94,258 1,309 Total $ 74,190 $ 833 $ 20,791 $ 481 $ 94,981 $ 1,314 December 30, 2017 Asset-backed securities $ 1,864 $ 4 $ 632 $ 1 $ 2,496 $ 5 Corporate bonds and direct obligations of government agencies 41,322 220 14,016 115 55,338 335 Total $ 43,186 $ 224 $ 14,648 $ 116 $ 57,834 $ 340

Change in Accounting Estimate_2

Change in Accounting Estimate for Self-Insured Claims (Tables)	9 Months Ended
	Sep. 29, 2018
Effect of Increase in Cost of Insurance and Claims	The following table summarizes the effect of the increase in the cost of insurance claims resulting from unfavorable development of prior year self-insured claims estimates on operating income, net income attributable to Landstar System, Inc. and subsidiary and earnings per share attributable to Landstar System, Inc. and subsidiary amounts in the consolidated statements of income for the thirty-nine-week and thirteen-week periods ended September 29, 2018 and September 30, 2017 (in thousands, except per share amounts): Thirty Nine Weeks Ended Thirteen Weeks Ended September 29, 2018 September 30, 2017 September 29, 2018 September 30, 2017 Operating income $ 11,596 $ 1,327 $ 3,352 $ 1,124 Net income attributable to Landstar System, Inc. and subsidiary 8,755 825 2,531 699 Earnings per share attributable to Landstar System, Inc. and subsidiary $ 0.21 $ 0.02 $ 0.06 $ 0.02 Diluted earnings per share attributable to Landstar System, Inc. and subsidiary $ 0.21 $ 0.02 $ 0.06 $ 0.02

Recent Accounting Pronounceme_2

Recent Accounting Pronouncements (Tables)	9 Months Ended
	Sep. 29, 2018
Accounting Standards Update 2014-09
Adoption of New Accounting Standards	The cumulative effect of the changes made to our consolidated December 31, 2017 balance sheet for the adoption of ASU 2014-09 Balance at December 30, 2017 Adjustments Due to ASU 2014-09 Balance at December 31, 2017 Balance Sheet Assets Trade accounts receivable, net $ 631,164 $ 9,879 $ 641,043 Other current assets 14,394 (469 ) 13,925 Liabilities Accounts payable 285,132 8,637 293,769 Equity Retained earnings 1,611,158 773 1,611,931 In accordance with the new revenue standard requirements, the impact of adoption on our consolidated income statement and balance sheet was as follows (in thousands): For the Thirty Nine Weeks ended September 29, 2018 As Reported Balances Without 2014-09 Effect of Change Income statement Revenues Transportation $ 3,394,298 $ 3,390,242 $ 4,056 Insurance 38,495 38,495 — Costs and expenses Purchased transportation 2,658,710 2,655,491 3,219 Commissions to agents 275,828 275,538 290 Income taxes 56,279 56,145 134 Net income attributable to Landstar System, Inc. and subsidiary 187,025 186,612 413 September 29, 2018 As Reported Balances Without 2014-09 Effect of Change Balance Sheet Assets Trade accounts receivable, net $ 702,183 $ 688,248 $ 13,935 Other current assets 24,191 24,794 (603 ) Liabilities Accounts payable 313,728 301,582 12,146 Equity Retained earnings 1,779,680 1,778,494 1,186

Business Description - Addition

Business Description - Additional Information (Detail)	Sep. 29, 2018USD ($)
Accounting Standards Update 2014-09 | Retained Earnings
Description of Business [Line Items]
Cumulative adjustment to retained earnings	$ 773,000

Acquired Business and Noncont_2

Acquired Business and Noncontrolling Interests - Additional Information (Detail) - USD ($)	9 Months Ended
	Sep. 29, 2018	Dec. 30, 2017	Sep. 30, 2017
Goodwill	$ 38,560,000	$ 39,065,000	$ 39,914,000
Fletes Avella | Landstar Metro
Business combination, recognized identifiable assets acquired and liabilities assumed, liabilities		$ 1,900,000
Approximate ownership interest acquired by affiliates	21.00%
Goodwill	$ 7,900,000
Percentage of goodwill estimated to be deductible after purchase of noncontrolling interests by the company	100.00%
Fletes Avella | Landstar Servicios
Approximate ownership interest acquired by affiliates	21.00%

Share-based Payment Arrangeme_3

Share-based Payment Arrangements - Additional Information (Detail) $ in Thousands	Apr. 24, 2018shares	Sep. 29, 2018USD ($)EquityPlanshares	Sep. 30, 2017USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of employee equity incentive plans | EquityPlan		2
Income tax benefit realized on disqualifying dispositions of stock acquired by exercise of incentive stock options		$ 80	$ 310
Maximum percentage of target available for common share issuance	150.00%
Accounting Standards Update 2016-09
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Excess tax benefit from stock-based awards		$ 2,046	868
2013 Directors Stock Compensation Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock authorized for issuance | shares		115,000
Common stock reserved for issuance | shares		72,742
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards granted, shares | shares	9,324	65,494
Recognized share-based compensation expense		$ 11,303	2,254
Unrecognized compensation cost expected to be recognized over period, years		3 years 3 months 18 days
Non Vested Restricted Stock and Deferred Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards granted, shares | shares		22,803
Unrecognized compensation cost, other than options		$ 3,756
Unrecognized compensation cost expected to be recognized over period, years		2 years 3 months 18 days
Terms of award		The Company’s common stock on the date of grant. Shares of non-vested restricted stock are generally subject to vesting in three equal annual installments either on the first, second and third anniversary of the date of the grant or the third, fourth and fifth anniversary of the date of the grant, or 100% on the first anniversary of the date of the grant. For restricted stock awards granted under the 2013 DSCP plan, each recipient may elect to defer receipt of shares and instead receive restricted stock units (“Deferred Stock Units”), which represent contingent rights to receive shares of the Company’s common stock on the date of recipient separation from service from the Board of Directors, or, if earlier, upon a change in control event of the Company. Deferred Stock Units become vested 100% on the first anniversary of the date of the grant.
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total intrinsic value of stock options exercised during periods		$ 6,584	$ 5,303
Unrecognized compensation cost, stock options		0
Maximum | Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost, other than options		$ 23,100
2011 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock authorized for issuance | shares		6,000,000
2013 Directors Stock Compensation Plan | Deferred Stock Unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock vesting percentage		100.00%
Other Stock Compensation Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance | shares		4,439,761

Amounts Recognized in Financial

Amounts Recognized in Financial Statements with Respect to Plans (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2018	Sep. 30, 2017	Sep. 29, 2018	Sep. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total cost of the Plans during the period	$ 4,901	$ 1,423	$ 13,003	$ 3,660
Amount of related income tax benefit recognized during the period	(1,837)	(678)	(5,305)	(2,492)
Net cost of the Plans during the period	$ 3,064	$ 745	$ 7,698	$ 1,168

Schedule of Information on Rest

Schedule of Information on Restricted Stock Units (Detail) - Restricted Stock Units (RSUs) - $ / shares	Apr. 24, 2018	Sep. 29, 2018
Number of Shares
Beginning Balance		387,372
Granted	9,324	65,494
Vested		(67,971)
Forfeited		(92,880)
Ending Balance		292,015
Weighted Average Grant Date Fair Value
Beginning Balance		$ 55.75
Granted		96.08
Vested		53.92
Forfeited		52.36
Ending Balance		$ 66.30

Summary of Information Regardin

Summary of Information Regarding Stock Options (Detail) $ / shares in Units, $ in Thousands	9 Months Ended
	Sep. 29, 2018USD ($)$ / sharesshares
Number of Options
Beginning Balance, number of options | shares	189,040
Exercised, number of options | shares	(97,676)
Ending Balance, number of options | shares	91,364
Options exercisable at the ending, Number of Options | shares	90,364
Weighted Average Exercise Price per Share
Beginning Balance, Weighted Average Exercise Price per Share | $ / shares	$ 49.34
Exercised, Weighted Average Exercise Price per Share | $ / shares	48.38
Ending Balance, Weighted Average Exercise Price per Share | $ / shares	50.36
Options exercisable at September 29, 2018 | $ / shares	$ 50.27
Weighted Average Remaining Contractual Term (years)
Options outstanding at September 29, 2018	3 years 3 months 18 days
Options exercisable at September 29, 2018	3 years 3 months 18 days
Aggregate Intrinsic Value
Options outstanding at September 29,2018 | $	$ 6,546
Options exercisable at September 29, 2018 | $	$ 6,482

Schedule of Information on Non

Schedule of Information on Non - Vested Restricted Stock Units (Detail) - Non Vested Restricted Stock and Deferred Stock Units	9 Months Ended
	Sep. 29, 2018$ / sharesshares
Number of Shares and Deferred Stock Units
Beginning Balance | shares	54,755
Granted | shares	22,803
Vested | shares	(19,814)
Forfeited | shares	(1,757)
Ending Balance | shares	55,987
Weighted Average Grant Date Fair Value
Beginning Balance | $ / shares	$ 78.02
Granted | $ / shares	113.35
Vested | $ / shares	75.11
Forfeited | $ / shares	71.12
Ending Balance | $ / shares	$ 93.66

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail)	9 Months Ended		12 Months Ended
	Sep. 29, 2018	Sep. 30, 2017	Dec. 30, 2017
Income Taxes [Line Items]
Corporate income tax rate	21.00%		35.00%
Estimated annual effective income tax rate	24.50%	37.80%
Effective income tax rate	23.10%	34.50%

Reconciliation of Average Numbe

Reconciliation of Average Number of Common Shares and Common Share Equivalents Outstanding (Detail) - shares	3 Months Ended		9 Months Ended
	Sep. 29, 2018	Sep. 30, 2017	Sep. 29, 2018	Sep. 30, 2017
Weighted Average Number of Shares Outstanding Reconciliation [Abstract]
Average number of common shares outstanding	41,101,000	41,957,000	41,530,000	41,924,000
Incremental shares from assumed exercises of stock options	36,000	71,000	46,000	89,000
Average number of common shares and common share equivalents outstanding	41,137,000	42,028,000	41,576,000	42,013,000

Earnings Per Share - Additional

Earnings Per Share - Additional Information (Detail) - shares	9 Months Ended
	Sep. 29, 2018	Sep. 30, 2017
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Stock options excluded from calculation of diluted earnings per share, antidilutive	0	0

Additional Cash Flow Informat_2

Additional Cash Flow Information - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2018	Sep. 30, 2017	Sep. 29, 2018	Sep. 30, 2017
Supplemental Cash Flow Information [Abstract]
Income taxes paid			$ 56,083	$ 65,688
Interest paid			2,737	2,981
Acquired operating property by capital leases			21,397	14,760
Payment to acquire operating property	$ 3,204	$ 2,172	7,325	$ 8,800
Laredo, TX
Supplemental Cash Flow Information [Abstract]
Payment to acquire operating property			$ 2,162

Information Regarding Reportabl

Information Regarding Reportable Business Segments (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2018	Sep. 30, 2017	Sep. 29, 2018	Sep. 30, 2017	Dec. 30, 2017
Segment Reporting Information [Line Items]
External revenue	$ 1,202,081	$ 943,430	$ 3,432,793	$ 2,594,772
Internal revenue	7,496	7,335	30,413	29,773
Investment income	1,002	711	2,754	1,733
Operating income	87,068	60,567	245,647	173,919
Expenditures on long-lived assets	3,204	2,172	7,325	8,800
Goodwill	38,560	39,914	38,560	39,914	$ 39,065
Transportation Logistics
Segment Reporting Information [Line Items]
External revenue	1,188,737	931,692	3,394,298	2,559,847
Operating income	80,878	54,181	227,176	148,693
Expenditures on long-lived assets	3,204	2,172	7,325	8,800
Goodwill	38,560	39,914	38,560	39,914
Insurance
Segment Reporting Information [Line Items]
External revenue	13,344	11,738	38,495	34,925
Internal revenue	7,496	7,335	30,413	29,773
Investment income	1,002	711	2,754	1,733
Operating income	$ 6,190	$ 6,386	$ 18,471	$ 25,226

Segment Information - Additiona

Segment Information - Additional Information (Detail) - Customer	3 Months Ended		9 Months Ended
	Sep. 29, 2018	Sep. 30, 2017	Sep. 29, 2018	Sep. 30, 2017
Segment Reporting Information [Line Items]
Number of customers accounting for 10 percent or more of total revenue	0	0	0	0
No single customer accounted for benchmark percentage to be considered major customer	10.00%	10.00%	10.00%	10.00%

Components of and Changes in Ac

Components of and Changes in Accumulated Other Comprehensive Income, Net of Related Income Taxes (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2018	Sep. 30, 2017	Sep. 29, 2018	Sep. 30, 2017
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance			$ 650,672
Other comprehensive (loss)	$ 715	$ 631	(1,407)	$ 1,381
Ending Balance	723,841		723,841
Unrealized Holding Losses on Available-for-Sale Securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance			(144)
Other comprehensive (loss)			(876)
Ending Balance	(1,020)		(1,020)
Foreign Currency Translation
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance			(3,018)
Other comprehensive (loss)			(531)
Ending Balance	(3,549)		(3,549)
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance			(3,162)
Other comprehensive (loss)			(1,407)
Ending Balance	$ (4,569)		$ (4,569)

Investments - Additional Inform

Investments - Additional Information (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 29, 2018	Dec. 30, 2017
Debt Securities, Available-for-sale [Line Items]
Investments maximum maturity period	5 years
Unrealized losses, net of unrealized gains, on the investments in the bond portfolio	$ 1,299	$ 223

Amortized Cost and Fair Value o

Amortized Cost and Fair Value of Available-for-Sale Investments (Detail) - USD ($) $ in Thousands	Sep. 29, 2018	Dec. 30, 2017
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 112,991	$ 111,142
Gross Unrealized Gains	15	117
Gross Unrealized Losses	1,314	340
Fair Value	111,692	110,919
Money market investments
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	12,430	27,895
Fair Value	12,430	27,895
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	728	2,805
Gross Unrealized Losses	5	5
Fair Value	723	2,800
Corporate bonds and direct obligations of government agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	99,833	80,442
Gross Unrealized Gains	15	117
Gross Unrealized Losses	1,309	335
Fair Value	$ 98,539	$ 80,224

Schedule of Unrealized Loss on

Schedule of Unrealized Loss on Available-for-Sale Investments (Detail) - USD ($) $ in Thousands	Sep. 29, 2018	Dec. 30, 2017
Debt Securities, Available-for-sale [Line Items]
Available-for-sale investments with unrealized losses, Less than 12 months, Fair Value	$ 74,190	$ 43,186
Available-for-sale investments with unrealized losses, Less than 12 months, Unrealized Loss	833	224
Available-for-sale investments with unrealized losses, 12 months or longer, Fair Value	20,791	14,648
Available-for-sale investments with unrealized losses, 12 months or longer, Unrealized Loss	481	116
Available-for-sale investments with unrealized losses, Fair Value, Total	94,981	57,834
Available-for-sale investments with unrealized losses, Unrealized Loss, Total	1,314	340
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale investments with unrealized losses, Less than 12 months, Fair Value	300	1,864
Available-for-sale investments with unrealized losses, Less than 12 months, Unrealized Loss	2	4
Available-for-sale investments with unrealized losses, 12 months or longer, Fair Value	423	632
Available-for-sale investments with unrealized losses, 12 months or longer, Unrealized Loss	3	1
Available-for-sale investments with unrealized losses, Fair Value, Total	723	2,496
Available-for-sale investments with unrealized losses, Unrealized Loss, Total	5	5
Corporate bonds and direct obligations of government agencies
Debt Securities, Available-for-sale [Line Items]
Available-for-sale investments with unrealized losses, Less than 12 months, Fair Value	73,890	41,322
Available-for-sale investments with unrealized losses, Less than 12 months, Unrealized Loss	831	220
Available-for-sale investments with unrealized losses, 12 months or longer, Fair Value	20,368	14,016
Available-for-sale investments with unrealized losses, 12 months or longer, Unrealized Loss	478	115
Available-for-sale investments with unrealized losses, Fair Value, Total	94,258	55,338
Available-for-sale investments with unrealized losses, Unrealized Loss, Total	$ 1,309	$ 335

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail) $ in Thousands	Sep. 29, 2018USD ($)
Fletes Avella | Landstar Metro
Commitments and Contingencies Disclosure [Line Items]
Approximate ownership interest acquired by affiliates	21.00%
Fletes Avella | Landstar Servicios
Commitments and Contingencies Disclosure [Line Items]
Approximate ownership interest acquired by affiliates	21.00%
Revolving Credit Facility
Commitments and Contingencies Disclosure [Line Items]
Letters of credit outstanding	$ 34,370
Guarantee Payment of Insurance Claims
Commitments and Contingencies Disclosure [Line Items]
Letters of credit outstanding	62,457
Current Investments | Collateral Pledged [Member]
Commitments and Contingencies Disclosure [Line Items]
Investments providing collateral for letters of credit to guarantee insurance claims	40,203
Non-Current Investments
Commitments and Contingencies Disclosure [Line Items]
Total non-current investments	71,489
Non-Current Investments | Collateral Pledged [Member]
Commitments and Contingencies Disclosure [Line Items]
Investments providing collateral for letters of credit to guarantee insurance claims	$ 29,194

Effect of Increase in Cost of I

Effect of Increase in Cost of Insurance and Claims (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2018	Sep. 30, 2017	Sep. 29, 2018	Sep. 30, 2017
Change in Accounting Estimate [Line Items]
Operating income	$ 87,068	$ 60,567	$ 245,647	$ 173,919
Net income attributable to Landstar System, Inc. and subsidiary	$ 66,985	$ 42,443	$ 187,025	$ 112,336
Earnings per share attributable to Landstar System, Inc. and subsidiary	$ 1.63	$ 1.01	$ 4.50	$ 2.68
Diluted earnings per share attributable to Landstar System, Inc. and subsidiary	$ 1.63	$ 1.01	$ 4.50	$ 2.67
Development of Prior Year Self Insured Claims Estimates
Change in Accounting Estimate [Line Items]
Operating income	$ 3,352	$ 1,124	$ 11,596	$ 1,327
Net income attributable to Landstar System, Inc. and subsidiary	$ 2,531	$ 699	$ 8,755	$ 825
Earnings per share attributable to Landstar System, Inc. and subsidiary	$ 0.06	$ 0.02	$ 0.21	$ 0.02
Diluted earnings per share attributable to Landstar System, Inc. and subsidiary	$ 0.06	$ 0.02	$ 0.21	$ 0.02

Recent Accounting Pronounceme_3

Recent Accounting Pronouncements - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2018	Sep. 30, 2017	Sep. 29, 2018	Sep. 30, 2017
Product Information [Line Items]
Revenue	$ 1,202,081	$ 943,430	$ 3,432,793	$ 2,594,772
BCO Independent Contractor
Product Information [Line Items]
Consolidated revenue, percentage			44.00%
Truck Brokerage Carriers
Product Information [Line Items]
Consolidated revenue, percentage			49.00%
Railroads
Product Information [Line Items]
Consolidated revenue, percentage			3.00%
Air and Ocean Cargo Carriers
Product Information [Line Items]
Consolidated revenue, percentage			2.00%
BCO Independent Contractor and Truck Brokerage Carriers | Van Equipment
Product Information [Line Items]
Revenue			$ 2,086,523
BCO Independent Contractor and Truck Brokerage Carriers | Unsided/Platform Equipment
Product Information [Line Items]
Revenue			1,039,784
BCO Independent Contractor and Truck Brokerage Carriers | Less than Truckload
Product Information [Line Items]
Revenue			$ 76,448

Cumulative Effect of Changes Ma

Cumulative Effect of Changes Made to Consolidated Balance Sheet (Detail) - USD ($) $ in Thousands	Sep. 29, 2018	Dec. 31, 2017	Dec. 30, 2017
ASSETS
Trade accounts receivable, net	$ 702,183	$ 641,043	$ 631,164
Other current assets	24,191	13,925	14,394
Liabilities
Accounts payable	313,728	293,769	285,132
Equity
Retained earnings	1,779,680	1,611,931	1,611,158
Calculated under Revenue Guidance in Effect before Topic 606
ASSETS
Trade accounts receivable, net	688,248		631,164
Other current assets	24,794		14,394
Liabilities
Accounts payable	301,582		285,132
Equity
Retained earnings	1,778,494		$ 1,611,158
Difference between Revenue Guidance in Effect before and after Topic 606 | Accounting Standards Update 2014-09
ASSETS
Trade accounts receivable, net	13,935	9,879
Other current assets	(603)	(469)
Liabilities
Accounts payable	12,146	8,637
Equity
Retained earnings	$ 1,186	$ 773

New Revenue Standard Requiremen

New Revenue Standard Requirements Impact of Adoption on Consolidated Income Statement and Balance Sheet (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2018	Sep. 30, 2017	Sep. 29, 2018	Sep. 30, 2017	Dec. 31, 2017	Dec. 30, 2017
Revenues
Revenues	$ 1,202,081	$ 943,430	$ 3,432,793	$ 2,594,772
Costs and expenses
Purchased transportation	931,473	726,827	2,658,710	1,989,938
Commissions to agents	99,304	76,598	275,828	210,678
Income taxes	19,304	17,490	56,279	59,047
Net income attributable to Landstar System, Inc. and subsidiary	66,985	42,443	187,025	112,336
ASSETS
Trade accounts receivable, net	702,183		702,183		$ 641,043	$ 631,164
Other current assets	24,191		24,191		13,925	14,394
Liabilities
Accounts payable	313,728		313,728		293,769	285,132
Equity
Retained earnings	1,779,680		1,779,680		1,611,931	1,611,158
Transportation Logistics
Revenues
Revenues	1,188,737	931,692	3,394,298	2,559,847
Insurance
Revenues
Revenues	13,344	$ 11,738	38,495	$ 34,925
Calculated under Revenue Guidance in Effect before Topic 606
Costs and expenses
Purchased transportation			2,655,491
Commissions to agents			275,538
Income taxes			56,145
Net income attributable to Landstar System, Inc. and subsidiary			186,612
ASSETS
Trade accounts receivable, net	688,248		688,248			631,164
Other current assets	24,794		24,794			14,394
Liabilities
Accounts payable	301,582		301,582			285,132
Equity
Retained earnings	1,778,494		1,778,494			$ 1,611,158
Calculated under Revenue Guidance in Effect before Topic 606 | Transportation Logistics
Revenues
Revenues			3,390,242
Calculated under Revenue Guidance in Effect before Topic 606 | Insurance
Revenues
Revenues			38,495
Difference between Revenue Guidance in Effect before and after Topic 606 | Accounting Standards Update 2014-09
Costs and expenses
Purchased transportation			3,219
Commissions to agents			290
Income taxes			134
Net income attributable to Landstar System, Inc. and subsidiary			413
ASSETS
Trade accounts receivable, net	13,935		13,935		9,879
Other current assets	(603)		(603)		(469)
Liabilities
Accounts payable	12,146		12,146		8,637
Equity
Retained earnings	$ 1,186		1,186		$ 773
Difference between Revenue Guidance in Effect before and after Topic 606 | Transportation Logistics | Accounting Standards Update 2014-09
Revenues
Revenues			$ 4,056