Pension Plans and Postretirement Benefits - Schedule of Assumptions for Pensions Plan (Details) - U.S.	11 Months Ended	12 Months Ended
Nov. 30, 2018	Nov. 30, 2019
WilTel Plan
Projected benefit obligation:
Discount rate	4.35%	3.00%
Net periodic pension benefit cost:
Discount rate	3.51%	4.35%
Discount rate	7.00%	7.00%
Jefferies Group Plan
Projected benefit obligation:
Discount rate	4.30%	2.90%
Net periodic pension benefit cost:
Discount rate	3.60%	4.30%
Discount rate	6.25%	6.25%

Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-SubTopic 20
-Section 50
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- Definition

Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost of defined benefit plan.

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- Definition

Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
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