Consolidated Statements of Stockholders' Equity (Parenthetical) $ in Thousands	3 Months Ended
Mar. 31, 2018 USD ($)
One time effect of adoption of ASU 2014-09, Revenue from Contracts with Customers, tax	$ 329

Other Comprehensive Income Loss New Accounting Pronouncement Or Change In Accounting Principle Effect To Retained Earnings, Tax.

No definition available.

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Namespace Prefix:	sam_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration