XML 66 R45.htm IDEA: XBRL DOCUMENT v3.25.0.1

Note 16 - Retirement Benefit Plans (Tables)

12 Months Ended

Dec. 31, 2024

Notes Tables

Defined Benefit Plan, Plan with Projected Benefit Obligation in Excess of Plan Assets [Table Text Block]

​		2024				2023
Change in plan assets:
Fair value of plan assets as of January 1		$	696.4			$	660.5
Return on plan assets			(32.9	)			15.2
Employer contributions			2.4				2.2
Benefits paid			(19.5	)			(17.9	)
Settlements			(9.6	)			(3.2	)
Foreign currency translation			(11.7	)			39.6
Fair value of plan assets as of December 31			625.1				696.4
Change in benefit obligation:
Benefit obligation as of January 1			(611.1	)			(565.6	)
Interest cost			(27.2	)			(27.6	)
Settlements			9.6				3.2
Benefits paid		19.5					17.9
Actuarial gain/(loss)			42.1				(5.1	)
Foreign currency translation			10.3				(33.9	)
Benefit obligation as of December 31			(556.8	)			(611.1	)
Funded status as of year-end			68.3				85.3
Net retirement benefit asset recognized in the Consolidated Balance Sheets		$	68.3			$	85.3

Schedule of Amounts Recognized in Balance Sheet [Table Text Block]

​		December 31,
​		2024				2023
Retirement benefit assets recognized in the Consolidated Balance Sheets:
Janus Henderson Group UK Pension Scheme		$	70.3			$	87.6
Retirement benefit obligations recognized in the Consolidated Balance Sheets:		​				​
Janus Henderson Group unapproved pension scheme			(2.0	)			(2.3	)
Net retirement benefit asset recognized in the Consolidated Balance Sheets		$	68.3			$	85.3

Schedule of Assumptions Used in Determining Defined Benefit Obligation [Table Text Block]

​		December 31,
​		2024				2023
Discount rate			5.5	%			4.5	%
Inflation — Retail Price Index (“RPI”)			3.2	%			3.1	%
Inflation — Consumer Price Index (“CPI”)			2.5	%			2.5	%
Pension increases (RPI capped at 5% per annum (“p.a.”))			3.1	%			3.0	%
Pension increases (RPI capped at 2.5% p.a.)			2.1	%			2.1	%
Life expectancy of male aged 60 at accounting date			29.0				29.1
Life expectancy of male aged 60 in 15 years’ time			30.0				30.1

Schedule of Allocation of Plan Assets [Table Text Block]

​		December 31,
​		2024				2023
Cash and cash equivalents		$	2.9			$	19.9
Money market instruments			7.1				7.8
Bulk annuity policy			217.7				240.7
Fixed income investments			269.0				300.6
Equity investments			128.4				127.4
Total assets at fair value		$	625.1			$	696.4

Schedule of Defined Benefit Plans Disclosures [Table Text Block]

​		Fair value measurements using:												​
​		Quoted prices in				Significant				​				​
​		active markets for				other				Significant				​
​		identical assets				observable				unobservable				​
​		and liabilities				inputs				inputs				​
​		(Level 1)				(Level 2)				(Level 3)				Total
Cash and cash equivalents		$	2.9			$	—			$	—			$	2.9
Money market instruments			7.1				—				—				7.1
Bulk annuity contract			—				—				217.7				217.7
Fixed income investments			269.0				—				—				269.0
Equity investments			128.4				—				—				128.4
Total		$	407.4			$	—			$	217.7			$	625.1

​		Fair value measurements using:												​
​		Quoted prices in				Significant				​				​
​		active markets for				other				Significant				​
​		identical assets				observable				unobservable				​
​		and liabilities				inputs				inputs				​
​		(Level 1)				(Level 2)				(Level 3)				Total
Cash and cash equivalents		$	19.9			$	—			$	—			$	19.9
Money market instruments			7.8				—				—				7.8
Bulk annuity contract			—				—				240.7				240.7
Fixed income investments			300.6				—				—				300.6
Equity investments			127.4				—				—				127.4
Total		$	455.7			$	—			$	240.7			$	696.4

Schedule of Actuarial Gains and Losses [Table Text Block]

​		2024				2023
Opening accumulated unamortized actuarial loss as of January 1		$	(84.7	)		$	(70.4	)
Actuarial loss			(17.5	)			(18.8	)
Tax at source on current year actuarial gain			3.2				3.5
Prior service cost			0.4				0.5
Amortization of actuarial loss			1.3				0.5
Closing accumulated unamortized actuarial loss as of December 31		$	(97.3	)		$	(84.7	)

Schedule of Assumptions Used in Determining Net Periodic Benefit Cost [Table Text Block]

​		Year ended December 31,
​		2024				2023				2022
Interest cost		$	(27.2	)		$	(27.6	)		$	(16.9	)
Amortization of actuarial loss			(1.3	)			(0.5	)			—
Amortization of prior service cost			(0.4	)			(0.4	)			(0.4	)
Expected return on plan assets			26.7				28.7				13.8
Net periodic benefit credit (cost)			(2.2	)			0.2				(3.5	)
Contributions to money purchase section			(12.5	)			(11.6	)			(11.5	)
Total cost		$	(14.7	)		$	(11.4	)		$	(15.0	)

​		Year ended December 31,
​		2024				2023				2022
Discount rate			4.5	%			4.8	%			1.9	%
Inflation — RPI			3.1	%			3.3	%			3.4	%
Inflation — CPI			2.5	%			2.7	%			2.8	%
Pension increases (RPI capped at 5% p.a.)			3.0	%			3.2	%			3.3	%
Pension increases (RPI capped at 2.5% p.a.)			2.1	%			2.1	%			2.2	%
Expected return on plan assets			4.1	%			4.4	%			1.6	%
Amortization period for net actuarial gains at beginning of the year			27.0				28.0				29.0

Schedule of Expected Benefit Payments [Table Text Block]

2025			$	21.7
2026			$	22.9
2027			$	24.0
2028			$	24.7
2029			$	26.2
2030-2034			$	138.5

X

- Definition

Tabular disclosure of actuarial gains and losses.

+ References

No definition available.

+ Details

Name:	jhg_ScheduleOfActuarialGainsAndLossesTableTextBlock
Namespace Prefix:	jhg_
Data Type:	dtr-types:textBlockItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Tabular disclosure of the assumptions used to determine for the benefit obligation, including assumed discount rates, rate increase in compensation increase, and expected long-term rates of return on plan assets.

+ References

No definition available.

+ Details

Name:	jhg_ScheduleOfAssumptionsUsedInDeterminingDefinedBenefitObligationTableTextBlock
Namespace Prefix:	jhg_
Data Type:	dtr-types:textBlockItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Tabular disclosure of the assumptions used to determine for net benefit cost, including assumed discount rates, rate increase in compensation increase, and expected long-term rates of return on plan assets.

+ References

No definition available.

+ Details

Name:	jhg_ScheduleOfAssumptionsUsedInDeterminingNetPeriodicBenefitCostTableTextBlock
Namespace Prefix:	jhg_
Data Type:	dtr-types:textBlockItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Tabular disclosure of the major categories of plan assets of pension plans and/or other employee benefit plans. This information may include, but is not limited to, the target allocation of plan assets, the fair value of each major category of plan assets, and the level within the fair value hierarchy in which the fair value measurements fall.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 715
-SubTopic 20
-Subparagraph (d)(5)
-Name Accounting Standards Codification
-Paragraph 1
-Section 50
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

+ Details

Name:	us-gaap_ScheduleOfAllocationOfPlanAssetsTableTextBlock
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:textBlockItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Tabular disclosure of the amounts that are recognized in the balance sheet (or statement of financial position) for pension plans and/or other employee benefit plans, showing separately the assets and current and noncurrent liabilities (if applicable) recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

+ Details

Name:	us-gaap_ScheduleOfAmountsRecognizedInBalanceSheetTableTextBlock
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:textBlockItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Tabular disclosure of benefit obligation and plan assets for defined benefit pension plan with projected benefit obligation in excess of plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480482/715-20-55-17

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-3

+ Details

Name:	us-gaap_ScheduleOfBenefitObligationsInExcessOfFairValueOfPlanAssetsTableTextBlock
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:textBlockItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Tabular disclosure of one or more of the entity's defined benefit pension plans or one or more other defined benefit postretirement plans, separately for pension plans and other postretirement benefit plans including the entity's schedule of fair value of plan assets for defined benefit or other postretirement plans.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-SubTopic 20
-Topic 715
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480482/715-20-55-17

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-3

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-4

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-2

+ Details

Name:	us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTextBlock
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:textBlockItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Tabular disclosure of benefits expected to be paid by pension plans and/or other employee benefit plans in each of the next five fiscal years and in the aggregate for the five fiscal years thereafter.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 715
-SubTopic 20
-Subparagraph (f)
-Name Accounting Standards Codification
-Paragraph 1
-Section 50
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

+ Details

Name:	us-gaap_ScheduleOfExpectedBenefitPaymentsTableTextBlock
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:textBlockItemType
Balance Type:	na
Period Type:	duration

X

- References

No definition available.

+ Details

Name:	us-gaap_TableTextBlock
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration