Consolidated Statements of Financial Condition (Parenthetical)	Dec. 31, 2015 $ / shares shares	Dec. 31, 2014 $ / shares shares
Class 0 Units [Member]
Members' capital:
Capital units, issued (in units)	390,743.099	390,307.769
Capital units, outstanding (in units)	390,743.099	390,307.769
Capital units, value (in dollars per unit) | $ / shares	147.34	149.37
Class 2 Units [Member]
Members' capital:
Capital units, issued (in units)	171,170.918	178,245.791
Capital units, outstanding (in units)	171,170.918	178,245.791
Capital units, value (in dollars per unit) | $ / shares	109.91	113.58