Capital Stock - Summary of Information Concerning Currently Outstanding and Exercisable Options (Detail) (USD $)	12 Months Ended
Dec. 27, 2014
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number Outstanding	75,000
Weighted Average Remaining Contractual Life (Years)	3 years 6 months
Weighted Average Exercise Price	$ 7.28
Number Exercisable	73,000
Options Exercisable, Weighted Average Exercise Price	$ 6.95
Range One [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Option Price per share, Minimum	$ 5.05
Option Price per share, maximum	$ 5.67
Number Outstanding	21,000
Weighted Average Remaining Contractual Life (Years)	3 years 10 months 24 days
Weighted Average Exercise Price	$ 5.64
Number Exercisable	21,000
Options Exercisable, Weighted Average Exercise Price	$ 5.64
Range Two [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Option Price per share, Minimum	$ 6.9
Number Outstanding	44,000
Weighted Average Remaining Contractual Life (Years)	3 years
Weighted Average Exercise Price	$ 6.90
Number Exercisable	44,000
Options Exercisable, Weighted Average Exercise Price	$ 6.90
Range Three [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Option Price per share, Minimum	$ 7.74
Number Outstanding	6,000
Weighted Average Remaining Contractual Life (Years)	5 years
Weighted Average Exercise Price	$ 7.74
Number Exercisable	6,000
Options Exercisable, Weighted Average Exercise Price	$ 7.74
Range Four [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Option Price per share, Minimum	$ 19.37
Number Outstanding	4,000
Weighted Average Remaining Contractual Life (Years)	6 years
Weighted Average Exercise Price	$ 19.37
Number Exercisable	2,000
Options Exercisable, Weighted Average Exercise Price	$ 19.37

Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(iii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(i)-(ii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(i)-(ii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Weighted average remaining contractual term of outstanding stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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