Collateralized transactions - Schedule of Disaggregation of Gross Obligations by Class (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
U.S. Treasury securities		$ 643,410
Equity securities		$ 284,987
Overnight and Open
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
U.S. Treasury securities	$ 999,809
Equity securities	235,498
Gross amount of recognized liabilities for repurchase agreements and securities loaned	$ 1,235,307

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No definition available.

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Amount, before effects of master netting arrangements, of securities loaned to entities in exchange for collateral and funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-SubTopic 20
-Topic 210
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-Topic 860
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-Name Accounting Standards Codification
-Section 55
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-Publisher FASB
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-Topic 860
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-Section 50
-Paragraph 7
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481420/860-30-50-7

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- Definition

Amount, before effects of master netting arrangements, of securities loaned to entities in exchange for collateral. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 20
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-Section 50
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