Consolidated Statements of Financial Condition (Unaudited) (Parenthetical)	Mar. 31, 2019 $ / Unit shares	Dec. 31, 2018 $ / Unit shares
Class 0 Units [Member]
Members' capital:
Capital units, issued (in units)	123,312.164	125,660.811
Capital units, outstanding (in units)	123,312.164	125,660.811
Capital units, value (in dollars per unit) | $ / Unit	133.70	133.70
Class 2 Units [Member]
Members' capital:
Capital units, issued (in units)	109,922.506	116,424.562
Capital units, outstanding (in units)	109,922.506	116,424.562
Capital units, value (in dollars per unit) | $ / Unit	95.82	96.01