Property and Equipment - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 24, 2014	Sep. 25, 2013	Sep. 24, 2014	Sep. 25, 2013	Dec. 25, 2013
Property, Plant and Equipment [Abstract]
Depreciation expense	$ 2.9	$ 2.6	$ 8.3	$ 7.6
Gross value of assets under capital leases	1.8		1.8		1.9
Accumulated depreciation of assets under capital leases	1.7		1.7		1.7
Capital expenditures	8.6		19.0
Capital expenditures for restaurant remodeling	2.2		7.6
Capital expenditures for new restaurants	5.0		8.1
Capital expenditures for other corporate capital requirements	$ 1.4		$ 3.3

Amount before accumulated depreciation of leased physical assets used in the normal conduct of business to produce goods and services.

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- Definition

The total charge for the use of long-lived depreciable assets subject to a lease meeting the criteria for capitalization.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6455314&loc=d3e45014-112735

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 10

-Section 55

-Paragraph 40

-Subparagraph (Note 2)

-URI http://asc.fasb.org/extlink&oid=6584154&loc=d3e38371-112697

+ Details

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- Definition

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

+ Details

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- Definition

The cash outflow for acquisition of or capital improvements to properties held for investment (operating, managed, leased) or for use.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585

+ Details

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- Definition

The cash outflow for acquisition of or capital improvements on other tangible or intangible assets not otherwise defined in the taxonomy.

+ References

+ Details

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- Definition

The cash outflow for acquisition of or capital improvements of property, plant and equipment, used to produce goods or deliver services, and not otherwise defined in the taxonomy.

+ References

+ Details

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- Definition

The cash outflow for purchases of and capital improvements on property, plant and equipment (capital expenditures), software, and other intangible assets.

+ References

+ Details

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- Details

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