Variable Interest Entities (Narrative) (Details) - USD ($)	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Affordable housing tax credits and other tax benefits	$ 28,300,000	$ 22,700,000
Investment company, voluntary fee waived	2,000,000	$ 50,700,000
Contractual obligation to provide financial support	0
Fair value investments, seed capital investments	21,500,000		$ 19,900,000
Unfunded commitments	$ 0		$ 0

Fair Value Investments, Seed Capital Investments

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- Definition

Amount of affordable housing tax credits and other tax benefits recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 740
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=116633289&loc=SL49122993-202985

+ Details

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- Definition

The amount of unfunded commitments for which the entity is obligated, to those certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 6A
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=SL6742756-110258

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- Definition

Amount of financial support committed by investment company to investee that is contractually required.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 20
-Section 50
-Paragraph 15
-URI https://asc.fasb.org/extlink&oid=66023616&loc=SL35737432-115832

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- Definition

Amount of fee voluntarily waived by investment company.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 20
-Section 50
-Paragraph 7
-URI https://asc.fasb.org/extlink&oid=66023616&loc=d3e9046-115832

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- References

No definition available.

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