Janus Henderson High-Yield Fund Investment Objectives and Goals - Class A C S I N R T Shares [Member] - Janus Henderson High-Yield Fund	Jun. 30, 2026
Prospectus [Line Items]
Risk/Return [Heading]	<span style="color:#000000;font-family:Times New Roman;font-size:15.20pt;font-weight:bold;">Janus Henderson High-Yield Fund</span>
Objective [Heading]	<span style="color:#FFFFFF;font-family:Times New Roman;font-size:10.45pt;font-weight:bold;margin-left:0.0pt;text-transform:uppercase;">Investment Objectives</span>
Objective, Primary [Text Block]	Janus Henderson High-Yield Fund seeks to obtain high current income.
Objective, Secondary [Text Block]	Capital appreciation is a secondary investment objective when consistent with its primary investment objective.

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