Janus Henderson Research Portfolio Expense Example - Service Shares [Member] - Janus Henderson Research Portfolio - Service Shares	Dec. 31, 2025 USD ($)
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	$ 109
Expense Example, with Redemption, 3 Years	340
Expense Example, with Redemption, 5 Years	590
Expense Example, with Redemption, 10 Years	$ 1,306

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