XML 82 R69.htm IDEA: XBRL DOCUMENT v2.4.1.9
Soft Dollar Arrangements - Additional Information (Detail) (USD $)
In Thousands, unless otherwise specified
 3 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Soft Dollar Arrangements [Abstract]    
Soft dollar credits $ 235samg_SoftDollarCredits $ 264samg_SoftDollarCredits