Fair Value Measurements - Changes in Fair Value for All Assets Using Material Level of Unobservable (Level 3) Inputs (Details) - Level 3 - USD ($) $ in Thousands	9 Months Ended
Aug. 31, 2020	Aug. 31, 2019
Deconsolidated \| Lamington
Fair Value, Assets, Unobservable Input Reconciliation [Roll Forward]
Beginning balance		$ 128,795
Change in fair value		37,941
Transferred to consolidation		(166,736)
Ending balance		0
Investment in Limited Partnership
Fair Value, Assets, Unobservable Input Reconciliation [Roll Forward]
Beginning balance	$ 137,849
Change in fair value	20,601
Distributions	(6,000)
Ending balance	152,450
Changes in fair value included in earnings for the period relating to assets held at the end of the period	14,601
Life Finance \| Deconsolidated
Fair Value, Assets, Unobservable Input Reconciliation [Roll Forward]
Beginning balance		505,235
Sale of policies		(344,845)
Change in fair value		(16,841)
Premiums paid		69,827
Purchase of policies		0
Matured/lapsed/sold polices		(100,373)
Receivable for maturity of life settlement write off		17,800
Transfer to investment in limited partnership		(130,803)
Ending balance		0
Changes in fair value included in earnings for the period relating to assets held at the end of the period		0
Life Finance \| Consolidated
Fair Value, Assets, Unobservable Input Reconciliation [Roll Forward]
Beginning balance	1,297	1,172
Sale of policies	(2,040)
Gain on sale of life settlement	743
Change in fair value	0	(37)
Premiums paid	0	118
Purchase of policies		0
Matured/lapsed/sold polices		0
Ending balance	0	1,253
Changes in fair value included in earnings for the period relating to assets held at the end of the period	$ 0	$ (37)

Fair Value Measurement with Unobservable Inputs Reconciliation, Recurring Basis Asset Matured Policies

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- Definition

Fair Value Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transferred From (To) Investments

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No definition available.

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- Definition

Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers to Consolidation

+ References

No definition available.

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- Definition

Fair Value Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Distributions

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- Definition

Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) On Sale

+ References

No definition available.

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- Definition

Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Receivable For Maturity Of Life Settlements Write Offs

+ References

No definition available.

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- Definition

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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- Definition

Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

Amount of gain (loss) recognized in other comprehensive income (OCI) from asset measured at fair value on recurring basis using unobservable input (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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- Definition

Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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- Definition

Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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