Fair Value Disclosures - Assets carried at fair value on a recurring basis (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Fair Value Disclosures
Transfer of Assets from Level 1 to 2	$ 0	$ 0
Transfer of Assets from Level 2 to 1	0	0
Transfer of Liabilities from Level 1 to 2	0	0
Transfer of Liabilities from Level 2 to 1	0	0
Recurring
Fair Value Disclosures
Total assets	18,020	18,102
Total Liabilities	0	0
Recurring \| Mutual funds
Fair Value Disclosures
Total assets	18,020	18,102
Level 1 \| Recurring
Fair Value Disclosures
Total assets	18,020	18,102
Level 1 \| Recurring \| Mutual funds
Fair Value Disclosures
Total assets	$ 18,020	$ 18,102

Amounts of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

No definition available.

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- Definition

Amounts of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

+ References

No definition available.

+ Details

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- Definition

Amounts of transfers of liabilities measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

+ References

No definition available.

+ Details

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- Definition

Amounts of transfers of liabilities measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

+ References

No definition available.

+ Details

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-3

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- Definition

Fair value of financial and nonfinancial obligations.

+ References

+ Details

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