Organization and Basis of Presentation	12 Months Ended
Nov. 30, 2017
Accounting Policies [Abstract]
Organization and Basis of Presentation	Organization and Basis of Presentation Organization Jefferies Group LLC is the largest independent U.S.-headquartered global full service, integrated securities and investment banking firm. The accompanying Consolidated Financial Statements represent the accounts of Jefferies Group LLC and all our subsidiaries (together “we” or “us”). The subsidiaries of Jefferies Group LLC include Jefferies LLC (“Jefferies”), Jefferies International Limited, Jefferies Hong Kong Limited, Jefferies Financial Services, Inc., Jefferies Funding LLC, Jefferies Leveraged Credit Products, LLC and all other entities in which we have a controlling financial interest or are the primary beneficiary. On April 9, 2015, we entered into an agreement to transfer certain of the client activities of our Futures business to Société Générale S.A. and initiated a plan to substantially exit the remaining aspects of our Futures business. During the second quarter of 2016, we completed the exit of the Futures business. For further information on the exit of the Futures business, refer to Note 20, Exit Costs. In November 2017, Jefferies Execution Services, Inc. merged with and into Jefferies, with Jefferies as the surviving entity. Jefferies Group LLC is an indirect wholly owned subsidiary of publicly traded Leucadia National Corporation (“Leucadia”). Leucadia does not guarantee any of our outstanding debt securities. Our 3.875% Convertible Senior Debentures due 2029 (principal amount of $345.0 million) (the “debentures”) were convertible into Leucadia common shares. $20.2 million of these debentures were called at November 1, 2017. At November 22, 2017, all of the remaining convertible debentures were called for optional redemption, with a redemption date of January 5, 2018, at a redemption price equal to 100% of the principal amount of the convertible debentures redeemed, plus accrued and unpaid interest to, but excluding, the redemption date. All of these remaining convertible debentures were redeemed on January 5, 2018 (see Note 12, Long-Term Debt, for further details). Jefferies Group LLC is a Securities and Exchange Commission (“SEC”) reporting company, filing annual, quarterly and periodic financial reports. Richard Handler, our Chief Executive Officer and Chairman, is the Chief Executive Officer of Leucadia, as well as a Director of Leucadia. Brian P. Friedman, our Chairman of the Executive Committee, is Leucadia’s President and a Director of Leucadia. We operate in two reportable business segments, Capital Markets and Asset Management. For further information on our reportable business segments, refer to Note 18, Segment Reporting. Basis of Presentation The accompanying Consolidated Financial Statements have been prepared in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”) for financial information. We have made a number of estimates and assumptions relating to the reporting of assets and liabilities, the disclosure of contingent assets and liabilities and the reported amounts of revenues and expenses during the reporting period to prepare these consolidated financial statements in conformity with U.S. GAAP. The most important of these estimates and assumptions relate to fair value measurements, compensation and benefits, goodwill and intangible assets, the ability to realize certain deferred tax assets and the recognition and measurement of uncertain tax positions. Although these and other estimates and assumptions are based on the best available information, actual results could be materially different from these estimates. Consolidation Our policy is to consolidate all entities that we control by ownership of a majority of the outstanding voting stock. In addition, we consolidate entities that meet the definition of a variable interest entity (“VIE”) for which we are the primary beneficiary. The primary beneficiary is the party who has the power to direct the activities of a VIE that most significantly impact the entity’s economic performance and who has an obligation to absorb losses of the entity or a right to receive benefits from the entity that could potentially be significant to the entity. For consolidated entities that are less than wholly owned, the third-party’s holding of equity interest is presented as Noncontrolling interests in our Consolidated Statements of Financial Condition and Consolidated Statements of Changes in Equity. The portion of net earnings attributable to the noncontrolling interests is presented as Net earnings to noncontrolling interests in our Consolidated Statements of Earnings. In situations in which we have significant influence, but not control, of an entity that does not qualify as a VIE, we apply either the equity method of accounting or fair value accounting pursuant to the fair value option election under U.S. GAAP, with our portion of net earnings or gains and losses recorded in Other revenues or Principal transaction revenues, respectively. We also have formed nonconsolidated investment vehicles with third-party investors that are typically organized as partnerships or limited liability companies and are carried at fair value. We act as general partner or managing member for these investment vehicles and have generally provided the third-party investors with termination or “kick-out” rights. Intercompany accounts and transactions are eliminated in consolidation.

Organization and Basis of Presentation

Organization

Jefferies Group LLC is the largest independent U.S.-headquartered global full service, integrated securities and investment banking firm. The accompanying Consolidated Financial Statements represent the accounts of Jefferies Group LLC and all our subsidiaries (together “we” or “us”). The subsidiaries of Jefferies Group LLC include Jefferies LLC (“Jefferies”), Jefferies International Limited, Jefferies Hong Kong Limited, Jefferies Financial Services, Inc., Jefferies Funding LLC, Jefferies Leveraged Credit Products, LLC and all other entities in which we have a controlling financial interest or are the primary beneficiary. On April 9, 2015, we entered into an agreement to transfer certain of the client activities of our Futures business to Société Générale S.A. and initiated a plan to substantially exit the remaining aspects of our Futures business. During the second quarter of 2016, we completed the exit of the Futures business. For further information on the exit of the Futures business, refer to Note 20, Exit Costs. In November 2017, Jefferies Execution Services, Inc. merged with and into Jefferies, with Jefferies as the surviving entity.

Jefferies Group LLC is an indirect wholly owned subsidiary of publicly traded Leucadia National Corporation (“Leucadia”). Leucadia does not guarantee any of our outstanding debt securities. Our 3.875% Convertible Senior Debentures due 2029 (principal amount of $345.0 million) (the “debentures”) were convertible into Leucadia common shares. $20.2 million of these debentures were called at November 1, 2017. At November 22, 2017, all of the remaining convertible debentures were called for optional redemption, with a redemption date of January 5, 2018, at a redemption price equal to 100% of the principal amount of the convertible debentures redeemed, plus accrued and unpaid interest to, but excluding, the redemption date. All of these remaining convertible debentures were redeemed on January 5, 2018 (see Note 12, Long-Term Debt, for further details). Jefferies Group LLC is a Securities and Exchange Commission (“SEC”) reporting company, filing annual, quarterly and periodic financial reports. Richard Handler, our Chief Executive Officer and Chairman, is the Chief Executive Officer of Leucadia, as well as a Director of Leucadia. Brian P. Friedman, our Chairman of the Executive Committee, is Leucadia’s President and a Director of Leucadia.

We operate in two reportable business segments, Capital Markets and Asset Management. For further information on our reportable business segments, refer to Note 18, Segment Reporting.

Basis of Presentation

The accompanying Consolidated Financial Statements have been prepared in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”) for financial information.

We have made a number of estimates and assumptions relating to the reporting of assets and liabilities, the disclosure of contingent assets and liabilities and the reported amounts of revenues and expenses during the reporting period to prepare these consolidated financial statements in conformity with U.S. GAAP. The most important of these estimates and assumptions relate to fair value measurements, compensation and benefits, goodwill and intangible assets, the ability to realize certain deferred tax assets and the recognition and measurement of uncertain tax positions. Although these and other estimates and assumptions are based on the best available information, actual results could be materially different from these estimates.

Consolidation

Our policy is to consolidate all entities that we control by ownership of a majority of the outstanding voting stock. In addition, we consolidate entities that meet the definition of a variable interest entity (“VIE”) for which we are the primary beneficiary. The primary beneficiary is the party who has the power to direct the activities of a VIE that most significantly impact the entity’s economic performance and who has an obligation to absorb losses of the entity or a right to receive benefits from the entity that could potentially be significant to the entity. For consolidated entities that are less than wholly owned, the third-party’s holding of equity interest is presented as Noncontrolling interests in our Consolidated Statements of Financial Condition and Consolidated Statements of Changes in Equity. The portion of net earnings attributable to the noncontrolling interests is presented as Net earnings to noncontrolling interests in our Consolidated Statements of Earnings.

In situations in which we have significant influence, but not control, of an entity that does not qualify as a VIE, we apply either the equity method of accounting or fair value accounting pursuant to the fair value option election under U.S. GAAP, with our portion of net earnings or gains and losses recorded in Other revenues or Principal transaction revenues, respectively. We also have formed nonconsolidated investment vehicles with third-party investors that are typically organized as partnerships or limited liability companies and are carried at fair value. We act as general partner or managing member for these investment vehicles and have generally provided the third-party investors with termination or “kick-out” rights.

Intercompany accounts and transactions are eliminated in consolidation.