Fair Value Measurements (Summarize Changes in Level 3 Assets) (Details) - USD ($)	9 Months Ended	12 Months Ended
Sep. 30, 2022	Dec. 31, 2021	Dec. 31, 2020
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Assets, impairments		$ 0
Securities transferred into or out of level 3, net	$ 0
Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Assets, beginning balance	20,590,000	19,546,000
Assets, earnings	(6,462,000)	613,000
Assets, other comprehensive income	0	0
Impairment of Intangible Assets (Excluding Goodwill)	0
Assets, purchases	5,611,000	2,000,000
Assets, (sales)	(925,000)	(1,569,000)
Assets, maturities	0	0
Assets. transfers out		0
Securities transferred into or out of level 3, net	0
Assets, ending balance	18,814,000	20,590,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability Value		0	$ 0
Liabilities, earnings	0	1,000
Liabilities, other comprehensive income	0	0
Liabilities, impairments	0	0
Liabilities, purchases	0	(1,000)
Liabilities, (sales)	0	0
Liabilities, maturities	0	0
Liabilities, transfers out	0	0
Level 3 \| Debt securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Assets, beginning balance	0	1,000,000
Assets, earnings		0
Assets, other comprehensive income		0
Assets, impairments		0
Assets, purchases		0
Assets, (sales)		(1,000,000)
Assets, maturities		0
Assets. transfers out		0
Assets, ending balance		0
Level 3 \| Arbitrage trading account
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Assets, beginning balance	20,590,000	18,546,000
Assets, earnings	(6,303,000)	605,000
Assets, other comprehensive income	0	0
Assets, impairments	0	0
Assets, purchases	925,000	2,000,000
Assets, (sales)	(925,000)	(561,000)
Assets, maturities	0	0
Assets. transfers out	0	0
Assets, ending balance	14,287,000	20,590,000
Level 3 \| Common stock
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Assets, beginning balance	9,294,000	9,215,000
Assets, earnings	(6,303,000)	640,000
Assets, other comprehensive income	0	0
Assets, impairments	0	0
Assets, purchases	0	0
Assets, (sales)	0	(561,000)
Assets, maturities	0	0
Assets. transfers out	0	0
Assets, ending balance	2,991,000	9,294,000
Level 3 \| Preferred stocks
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Assets, beginning balance	11,296,000	9,331,000
Assets, earnings	0	(35,000)
Assets, other comprehensive income	0	0
Assets, impairments	0	0
Assets, purchases	925,000	2,000,000
Assets, (sales)	(925,000)	0
Assets, maturities	0	0
Assets. transfers out	0	0
Assets, ending balance	11,296,000	11,296,000
Level 3 \| Arbitrage trading account
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Assets, beginning balance	0	0
Assets, earnings	(159,000)	8,000
Assets, other comprehensive income	0	0
Impairment of Intangible Assets (Excluding Goodwill)	0
Assets, impairments		0
Assets, purchases	4,686,000	0
Assets, (sales)	0	(8,000)
Assets, maturities	0	0
Assets. transfers out		0
Securities transferred into or out of level 3, net	0
Assets, ending balance	4,527,000	0
Level 3 \| Corporate
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Assets, beginning balance	$ 0	1,000,000
Assets, earnings		0
Assets, other comprehensive income		0
Impairment of Intangible Assets (Excluding Goodwill)		0
Assets, purchases		0
Assets, (sales)		(1,000,000)
Assets, maturities		0
Securities transferred into or out of level 3, net		0
Assets, ending balance		$ 0

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

No definition available.

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- Definition

Amount of transfers of financial instrument classified as a liability out of level 3 of the fair value hierarchy.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
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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

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-Publisher FASB
-Name Accounting Standards Codification
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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

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-Publisher FASB
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-SubTopic 10
-Section 50
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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.

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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

Amount of transfer of financial instrument classified as an asset into (out of) level 3 of the fair value hierarchy.

+ References

No definition available.

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Amount of transfers of financial instrument classified as an asset out of level 3 of the fair value hierarchy.

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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.

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- Definition

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

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-Name Accounting Standards Codification
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Amount of gain (loss) recognized in other comprehensive income (OCI) from liability measured at fair value on recurring basis using unobservable input (level 3).

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

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

+ References

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-Publisher FASB
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-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

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- Definition

The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of an intangible asset (excluding goodwill) to fair value.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Impairment

+ References

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Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liabilities, Impairment

+ References

No definition available.

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