Self insurance retained aggregate liability.

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- Definition

Self Insurance Retained Liability

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No definition available.

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- Definition

Significant Accounting Policies [Line Items]

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No definition available.

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- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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- Definition

Date the declared dividend will be paid, in CCYY-MM-DD format.

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- Definition

The per share amount of a dividend declared, but not paid, as of the financial reporting date.

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- Definition

Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Date the dividend to be paid was declared, in CCYY-MM-DD format.

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- Definition

Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

+ References

No definition available.

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- Definition

Amount of cumulative effect of the change in accounting principle or new accounting pronouncement on retained earnings or other components of equity or net assets in the statement of financial position as of the beginning of the earliest period presented.

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- Definition

Number of reporting units tested for impairment of goodwill. A reporting unit is an operating segment or one level below an operating segment.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Significant Accounting Policies - Additional Information (Detail)	12 Months Ended
	Dec. 29, 2018 USD ($) shares	Dec. 30, 2017 USD ($) $ / shares shares	Dec. 31, 2016 shares
Significant Accounting Policies [Line Items]
Number of reporting units	2
Stock options excluded from calculation of diluted earnings per share, antidilutive \| shares	0	0	0
Dividends payable per share \| $ / shares		$ 1.50
Dividend payable date		Jan. 26, 2018
Dividend record date		Jan. 12, 2018
Dividends payable		$ 62,985,000
Dividend declared date		Dec. 11, 2017
Accounting Standards Update 2014-09 \| Retained Earnings
Significant Accounting Policies [Line Items]
Cumulative adjustment to retained earnings	$ 773,000
Buildings And Improvements
Significant Accounting Policies [Line Items]
Depreciated life	30 years
Trailing Equipment \| Maximum
Significant Accounting Policies [Line Items]
Depreciated life	10 years
Trailing Equipment \| Minimum
Significant Accounting Policies [Line Items]
Depreciated life	7 years
Hardware And Software \| Maximum
Significant Accounting Policies [Line Items]
Depreciated life	7 years
Hardware And Software \| Minimum
Significant Accounting Policies [Line Items]
Depreciated life	3 years
Commercial Trucking Claims \| Maximum
Significant Accounting Policies [Line Items]
Company retained liability per claim	$ 5,000,000
Commercial Trucking Claims \| Maximum \| Additional Retained Liability for Claims on or after May 1, 2016 through April 30, 2017
Significant Accounting Policies [Line Items]
Company retained aggregate liability	700,000
Commercial Trucking Claims \| Maximum \| Additional Retained Liability for Claims on or after May 1, 2017 through April 30, 2018
Significant Accounting Policies [Line Items]
Company retained aggregate liability	500,000
Commercial Trucking Claims \| Maximum \| Additional Retained Liability for Claims on or after May 1, 2018 through April 30, 2019
Significant Accounting Policies [Line Items]
Company retained aggregate liability	350,000
General Liability Claim \| Maximum
Significant Accounting Policies [Line Items]
Company retained liability per claim	1,000,000
Workers' Compensation Claim \| Maximum
Significant Accounting Policies [Line Items]
Company retained liability per claim	250,000
Cargo Claim \| Maximum
Significant Accounting Policies [Line Items]
Company retained liability per claim	$ 250,000