Selected Quarterly Financial Data (Unaudited) - Summary of Unaudited Quarterly Statements of Earnings (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Nov. 30, 2016	Aug. 31, 2016	May 31, 2016	Feb. 29, 2016	Nov. 30, 2015	Aug. 31, 2015	May 31, 2015	Feb. 28, 2015	Nov. 30, 2016	Nov. 30, 2015	Nov. 30, 2014
Quarterly Financial Information Disclosure [Abstract]
Total revenues	$ 939,960	$ 863,841	$ 936,917	$ 493,105	$ 701,930	$ 781,123	$ 1,008,510	$ 783,332	$ 3,233,823	$ 3,274,895	$ 3,846,265
Net revenues	741,769	654,450	719,408	298,987	513,087	578,928	791,554	591,672	2,414,614	2,475,241	2,990,138
Income before income tax expense	96,529	80,722	102,597	(249,876)	9,538	7,093	84,712	12,884	$ 29,972	$ 114,227	$ 303,021
Net earnings (loss) attributable to Jefferies Group LLC	$ 87,180	$ 41,169	$ 53,898	$ (166,813)	$ 19,962	$ 2,057	$ 59,833	$ 11,682