v3.26.3
Janus Henderson Global Allocation Fund - Moderate Average Annual Total Returns - Class A C S I T Shares [Member]
 12 Months Ended 60 Months Ended 120 Months Ended
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
MSCI All Country World IndexSM (reflects no deduction for expenses, fees, or taxes, except foreign withholding taxes)[Member]      
Prospectus [Line Items]      
Average Annual Return, Percent 22.34% 11.19% 11.72%
Global Moderate Allocation Index (Hedged) (reflects no deduction for expenses, fees, or taxes, except any applicable foreign withholding taxes)[Member]      
Prospectus [Line Items]      
Average Annual Return, Percent 15.15% 6.88% 8.13%
Global Moderate Allocation Index (Unhedged) (reflects no deduction for expenses, fees, or taxes, except any applicable foreign withholding taxes)[Member]      
Prospectus [Line Items]      
Average Annual Return, Percent 16.60% 5.79% 7.62%
Class A | Return Before Taxes[Member]      
Prospectus [Line Items]      
Average Annual Return, Percent [1] 8.94% 3.11% 5.52%
Class C | Return Before Taxes[Member]      
Prospectus [Line Items]      
Average Annual Return, Percent [2] 13.61% 3.57% 5.39%
Class S | Return Before Taxes[Member]      
Prospectus [Line Items]      
Average Annual Return, Percent 15.24% 4.11% 5.93%
Class I | Return Before Taxes[Member]      
Prospectus [Line Items]      
Average Annual Return, Percent 15.77% 4.56% 6.38%
Class T | After Taxes on Distributions      
Prospectus [Line Items]      
Average Annual Return, Percent 13.85% 2.94% 4.88%
Class T | After Taxes on Distributions and Sales      
Prospectus [Line Items]      
Average Annual Return, Percent [3] 10.09% 3.10% 4.66%
Class T | Return Before Taxes[Member]      
Prospectus [Line Items]      
Average Annual Return, Percent 15.59% 4.44% 6.25%
[1] Calculated assuming maximum permitted sales loads.
[2] The one year return is calculated to include the contingent deferred sales charge.
[3] If the Fund incurs a loss, which generates a tax benefit, the Return After Taxes on Distributions and Sale of Fund Shares may exceed the Fund’s other return figures.