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Commitments and Contingencies (Narrative) (Details) $ in Thousands	Dec. 31, 2023 USD ($)
Total contractually obligated investments
Contractual Obligation	$ 413,800
Alternative and Other Investments
Contractual Obligation	254,300
Non-publicly traded collateralized loan obligations in our fixed income securities portfolio
Contractual Obligation	86,700
Non-publicly traded common stock within our equity portfolio
Contractual Obligation	40,000
Commercial Mortgage Loans SIGI
Contractual Obligation	800
Privately placed corporate securities
Contractual Obligation	$ 32,000

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- Definition

Amount of contractual obligation, including, but not limited to, long-term debt, lease obligation, purchase obligation, and other commitments.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-3

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