Employee Retirement Plans and Post-Retirement Medical Benefits - Additional Information (Detail) $ in Thousands		1 Months Ended	12 Months Ended
	Apr. 01, 2023	Jan. 31, 2020	Dec. 30, 2023 USD ($) CompensationPlan	Dec. 31, 2022 USD ($)	Dec. 25, 2021 USD ($)
Retiree Medical Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Unfunded projected pension benefits			$ (828)	$ (757)
Non-Union Plans | Boston Beer 401 (k) Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Eligibility timing			eligible to participate in the Plan immediately upon employment
Voluntary contributions of annual compensation			60.00%
Employer matching contribution percentage			5.00%
Contributions Plan			$ 8,800	$ 7,600	$ 7,400
Non-Union Plans | Boston Beer 401 (k) Plan | Company's match thereafter
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer matching contribution percentage		3.00%
Employer match percentage		100.00%
Non-Union Plans | Boston Beer 401 (k) Plan | Company's match for the first 3% of the eligible participants contribute
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer matching contribution percentage		2.00%
Employer match percentage		50.00%
Non-Union Plans | Boston Beer 401 (k) Plan | Company's match for the first 5% of the eligible contribution
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer matching contribution percentage	5.00%
Employer match percentage	100.00%
Union Plans
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Number of retirement plans | CompensationPlan			3
Union Plans | Retiree Medical Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Eligibility period			20 years
Time required for eligibility			5 years
Benefit obligation, discount rate			5.03%	5.22%
Benefit obligation, rate of compensation increase			2.50%	2.50%
Percentage paid for coverage			100.00%
Union Plans | Retiree Medical Plan | Minimum
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Voluntarily retirement age			57 years
Union Plans | Retiree Medical Plan | Local #20 member
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Time required for eligibility			7 years
Retiree Medical Plan, last years of employment			10 years
Voluntarily retirement age			65 years
Union Plans | Retiree Medical Plan | Local #20 member | Minimum
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Eligibility period			20 years
Union Plans | Samuel Adams Cincinnati Brewery 401 (k) Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Eligibility timing			all members of Local 20 upon commencement of employment or, if later, attaining age 21.
Voluntary contributions of annual compensation			60.00%