Benefit Plans - Changes in Projected Benefit Obligation and Components of Net Periodic Pension Costs (Details) - United States - USD ($) $ in Thousands	12 Months Ended
Nov. 30, 2019	Nov. 30, 2018	Nov. 30, 2017
Change in projected benefit obligation:
Projected benefit obligation, beginning of period	$ 54,724	$ 60,559
Service cost	500	400	$ 450
Interest cost	2,303	2,129	2,232
Actuarial (gains)/losses	9,606	(3,777)
Administrative expenses paid	(467)	(502)
Benefits paid	(3,444)	(952)
Settlements	0	(3,133)
Projected benefit obligation, end of period	63,222	54,724	60,559
Change in plan assets:
Fair value of assets, beginning of period	48,176	52,949
Benefits paid	(3,444)	(952)
Administrative expenses paid	(467)	(502)
Actual return on plan assets	10,715	(1,186)
Contributions	2,000	1,000
Settlements	0	(3,133)
Fair value of assets, end of period	56,980	48,176	$ 52,949
Funded status at end of period	$ (6,242)	$ (6,548)

Defined Benefit Plan Administrative Expenses Paid.

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Amount of increase (decrease) in plan assets of defined benefit plan from actual return (loss) determined by change in fair value of plan assets adjusted for contributions, benefit payments, and other expenses.

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Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan.

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Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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Amount of payment to participant of defined benefit plan which decreases benefit obligation. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of contribution received by defined benefit plan from employer which increases plan assets.

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Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

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Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status.

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Amount of cost recognized for passage of time related to defined benefit plan.

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Amount of payment to participant under defined benefit plan which decreases plan assets. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.

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Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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Amount of (increase) decrease to benefit obligation of defined benefit plan from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Includes, but is not limited to, lump-sum cash payment to participant in exchange for right to receive specified benefits, purchase of nonparticipating annuity contract and change from remeasurement.

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Amount of payment, which decreases plan assets of defined benefit plan, for irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Transaction constituting settlement includes, but is not limited to, making lump-sum cash payment to participant in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contract.

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