Janus International Group Annual report [Section 13 and 15(d), not S-K Item 405]

Subsequent Events (Details)

v3.25.4

Subsequent Events (Details) - USD ($) $ in Millions			12 Months Ended
Subsequent Events (Details) - USD ($) $ in Millions	Feb. 02, 2026	Jan. 08, 2026	Jan. 03, 2026	Dec. 28, 2024	Dec. 30, 2023
Subsequent Event [Line Items]
Payments to acquire businesses, net of cash acquired			$ 0.1	$ 59.4	$ 1.0
Subsequent Event \| Note Payable, Amendment Number 8 First Lien \| Notes Payable
Subsequent Event [Line Items]
Increase in basis spread	0.50%
Subsequent Event \| Note Payable, Amendment Number 8 First Lien \| Base Rate \| Notes Payable
Subsequent Event [Line Items]
Variable rate	1.00%
Subsequent Event \| Note Payable, Amendment Number 8 First Lien \| SOFR \| Notes Payable
Subsequent Event [Line Items]
Variable rate	2.00%
Subsequent Event \| Kiwi Acquisition
Subsequent Event [Line Items]
Cash paid		$ 97.2

- Definition

Debt Instrument, Increase (Decrease) Basis Spread on Variable Rate

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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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