Self insurance retained aggregate liability.

No definition available.

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- Definition

Self Insurance Retained Liability

+ References

No definition available.

+ Details

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- Definition

Significant Accounting Policies [Line Items]

+ References

No definition available.

+ Details

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586

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- Definition

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

+ References

+ Details

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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=82887183&loc=d3e6935-107765

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.20)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

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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.

+ Details

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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.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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Significant Accounting Policies - Additional Information (Detail)	12 Months Ended
	Dec. 30, 2017 USD ($) $ / shares shares	Dec. 31, 2016 shares	Dec. 26, 2015 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
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
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