Fair Value Measurements - Changes in Fair Value for All Assets Using Material Level of Unobservable (Level 3) Inputs (Details) - USD ($) $ in Thousands	3 Months Ended
Feb. 29, 2020	Feb. 28, 2019
Lamington
Fair Value, Assets, Unobservable Input Reconciliation [Roll Forward]
Increase in basis investment		$ 711
Level 3 \| Deconsolidated \| Lamington
Fair Value, Assets, Unobservable Input Reconciliation [Roll Forward]
Beginning balance		128,795
Change in fair value		(33,965)
Increase in basis investment		711
Ending balance		95,541
Level 3 \| Investment in Limited Partnership
Fair Value, Assets, Unobservable Input Reconciliation [Roll Forward]
Beginning balance	$ 137,849
Change in fair value	7,351
Distributions	(1,999)
Ending balance	143,201
Changes in fair value included in earnings for the period relating to assets held at the end of the period	5,351
Level 3 \| Life Finance \| Deconsolidated
Fair Value, Assets, Unobservable Input Reconciliation [Roll Forward]
Beginning balance		505,235
Change in fair value		(12,750)
Premiums paid		25,247
Purchase of policies		0
Matured/lapsed/sold polices		(23,000)
Ending balance		494,732
Changes in fair value included in earnings for the period relating to assets held at the end of the period		28,430
Level 3 \| 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	2
Premiums paid	0	39
Purchase of policies		0
Matured/lapsed/sold polices		0
Ending balance	0	1,213
Changes in fair value included in earnings for the period relating to assets held at the end of the period	$ 0	$ 1

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, Distributions

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- Definition

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

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- Definition

Investment Owned, Recognized Realized Appreciation

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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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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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