Note 3 - Consolidation - VREs (Details) - USD ($) $ in Millions |
Jun. 30, 2025 |
Mar. 31, 2025 |
Dec. 31, 2024 |
|---|---|---|---|
| Investments | $ 380.7 | $ 337.1 | |
| Cash and cash equivalents | 882.6 | 1,217.2 | |
| Other current assets | $ 153.0 | 134.5 | |
| Variable Rights Entity, Primary Beneficiary, Aggregated Disclosure [Member] | |||
| Investments | $ 148.1 | 132.5 | |
| Cash and cash equivalents | 12.2 | 26.3 | |
| Other current assets | 1.3 | 2.7 | |
| Accounts payable and accrued liabilities | (2.0) | (0.9) | |
| Total | 159.6 | 160.6 | |
| Redeemable noncontrolling interests in consolidated VREs | (30.2) | (22.7) | |
| JHG’s net interest in consolidated VREs | $ 129.4 | $ 137.9 |
| X | ||||||||||
- Definition Portion of equity (net assets) in a voting rights entities (VRE) not attributable, directly or indirectly, to the parent entity. That is, this is the portion of equity in a VRE that is attributable to the redeemable noncontrolling interest (previously referred to as minority interest). No definition available.
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- Definition The net carrying amount of the net interest in consolidated voting rights entities assets and liabilities excluding noncontrolling interest. No definition available.
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- Definition The net carrying amount of the Voting Rights Entity's assets and liabilities included in the reporting entity's statement of financial position. No definition available.
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- Definition Sum of the carrying values as of the balance sheet date of obligations incurred through that date and due within one year (or the operating cycle, if longer), including liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received, taxes, interest, rent and utilities, accrued salaries and bonuses, payroll taxes and fringe benefits. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Amount of cash and cash equivalent. Cash includes, but is not limited to, currency on hand, demand deposit with financial institution, and account with general characteristic of demand deposit. Cash equivalent includes, but is not limited to, short-term, highly liquid investment that is both readily convertible to known amount of cash and so near maturity that it presents insignificant risk of change in value because of change in interest rate. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of current assets classified as other. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of investments including trading securities, available-for-sale securities, held-to-maturity securities, and short-term investments classified as other and current. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Details
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