Investment in Limited Partnership - Reconciliation of Funds Received And Distributions From Collection Account (Details) $ in Thousands	3 Months Ended
Feb. 29, 2020 USD ($)
Funds Received And Distributions Paid From Collection Account [Roll Forward]
Balance at December 1, 2019	$ 13,007
Maturity proceeds received - face	33,126
Proceeds received - other	145
Total receipts	46,278
Less: Distribution to premium/expense account	26,867
Balance at February 29, 2020	$ 19,411

Funds Received And Distributions Paid From Collection Account [Roll Forward]

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Investments in and Advances to Affiliates, Collection Account

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Investments in and Advances to Affiliates, Distributions From Collected Amounts

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Investments in and Advances to Affiliates, Maturity Proceeds Received

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Investments in and Advances to Affiliates, Other Proceeds Received

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Investments in and Advances to Affiliates, Proceeds Received

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