Summary of Significant Accounting Policies - Additional Information (Detail)	12 Months Ended
	Dec. 26, 2015 USD ($) Customer	Dec. 27, 2014 USD ($) Customer	Dec. 28, 2013 USD ($) Customer	Aug. 26, 2013 USD ($)
Organization And Summary Of Significant Accounting Policies [Line Items]
Restricted cash	$ 456,000	$ 513,000
Number of individual customer accounted for more than ten percent of account receivable balance | Customer	0	0
Number of individual customers represented more than ten percent of revenues | Customer	0	0	0
Sales to foreign distributors as a percentage of total sales	4.00%
Provision for excess or expired inventory	$ 4,000,000	$ 6,100,000	$ 4,900,000
Decrease in refundable deposits for lost kegs and pallets	(900,000)	(1,000,000)
Decrease in gross property, plant and equipment	(1,200,000)	(1,800,000)
Decrease in property, plant and equipment related accumulated depreciation	(1,200,000)	(1,800,000)
Refundable deposits on kegs and pallets	17,100,000	18,200,000
Property, plant and equipment, net	409,926,000	381,569,000
Goodwill	3,683,000	3,683,000		$ 1,145,000
Deferred Revenue, Current	3,949,000	6,034,000
Shipping costs	62,200,000	62,600,000	50,300,000
Advertising and sales promotional expenditures	120,100,000	100,500,000	81,000,000
Amounts paid to customers	273,629,000	250,696,000	207,930,000
Deferred income taxes	6,983,000	8,685,000
Boston Beer Company Reporting Unit
Organization And Summary Of Significant Accounting Policies [Line Items]
Goodwill	1,400,000	1,400,000
A&S Brewing Collaborative Reporting Unit
Organization And Summary Of Significant Accounting Policies [Line Items]
Goodwill	2,300,000	2,300,000
Kegs
Organization And Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment, net	18,900,000	25,900,000
Distributors
Organization And Summary Of Significant Accounting Policies [Line Items]
Advertising and sales promotional expenditures	22,100,000	23,900,000	17,300,000
Amounts paid to distributors	33,200,000	28,500,000	23,100,000
Reduction in revenue related to advertising, promotional and selling expenses	16,600,000	18,700,000	13,400,000
Customers programs and incentives
Organization And Summary Of Significant Accounting Policies [Line Items]
Amounts paid to customers	$ 55,300,000	$ 52,400,000	$ 40,400,000