Annual report pursuant to Section 13 and 15(d)

Investments and Fair Value Measurements - Category of Financial Instruments Not Held at Fair Value (Parenthetical) (Detail)

v2.4.1.9
Investments and Fair Value Measurements - Category of Financial Instruments Not Held at Fair Value (Parenthetical) (Detail) (Money Market Funds, USD $)
Dec. 31, 2014
Money Market Funds
 
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]  
Quoted market price $ 1.00samg_QuotedMarketPricePerCommonShare
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