Commitments and Contingencies Disclosure [Line Items]

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- Definition

Lease Expiration Year

+ References

No definition available.

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- Definition

Number of Suppliers

+ References

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- Definition

Percentage Of Production Volumes

+ References

No definition available.

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- Definition

Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=77902758&loc=d3e41499-112717

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- Definition

Minimum amount of purchase arrangement in which the entity has agreed to expend funds to procure goods or services from a supplier.

+ References

No definition available.

+ Details

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- Definition

Amount of the recorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=77896938&loc=d3e25383-109308

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Period Type:	instant

- Details

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- Details

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- Details

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Commitments and Contingencies - Additional Information (Detail) $ in Millions	12 Months Ended
	Dec. 30, 2017 USD ($) Vendor	Dec. 31, 2016 USD ($)	Dec. 26, 2015 USD ($)
Operating Leases
Commitments and Contingencies Disclosure [Line Items]
Rent expense	$ 3.4	$ 3.8	$ 3.4
Lease expiration dates	2022
Minimum
Commitments and Contingencies Disclosure [Line Items]
Company's current brewing and packaging percentage	90.00%
Barley and Wheat
Commitments and Contingencies Disclosure [Line Items]
Number of suppliers \| Vendor	2
Purchase commitments outstanding	$ 13.7
Hops
Commitments and Contingencies Disclosure [Line Items]
Purchase commitments	48.5
Glass Bottles
Commitments and Contingencies Disclosure [Line Items]
Purchase commitments	$ 13.9