Business Combinations, Asset Acquisitions, and Joint Venture Formation (Details)			3 Months Ended			6 Months Ended			12 Months Ended
		Jul. 31, 2025 USD ($) $ / shares shares	Jun. 27, 2025 USD ($)		Jun. 28, 2024 USD ($)	Jun. 27, 2025 USD ($)		Jun. 28, 2024 USD ($)	Dec. 27, 2024 USD ($)
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Business Combination, Integration Related Costs			$ 22,600,000	[1]	$ 0	$ 43,100,000	[1]	$ 0
Separation Costs	[2]		2,200,000		$ 10,300,000	3,600,000		17,000,000.0
Transaction Services Agreement Revenue			2,200,000			5,200,000
Payments related to divestiture (Note 3)						(6,200,000)		$ 0
Transaction Incentive Plan | Therakos Divestiture
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Participant Compensation, Paid After the Next Twelve Months			14,600,000
Compensation Expense, Excluding Cost of Good and Service Sold			1,700,000			3,400,000
Accrued Bonuses			6,100,000			6,100,000			$ 2,700,000
Transaction Incentive Plan | Therakos Divestiture | Maximum
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Participant Compensation, Paid After the Next Twelve Months			16,400,000
Therakos Divestiture
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Proceeds from Divestiture of Businesses						$ 881,400,000			$ 887,600,000
Mallinckrodt & Endo Merger | Transaction Incentive Plan
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Participant Compensation, Paid After the Next Twelve Months			$ 93,900,000
Mallinckrodt & Endo Merger | Mallinckrodt | Subsequent Event
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Shares, Issued | shares		19,650,663
Business Acquisition, Share Price | $ / shares		$ 92.30
Equity Issued in Business Combination, Fair Value Disclosure		$ 1,813,800,000
Business Combination, Consideration Transferred		1,923,300,000
Mallinckrodt & Endo Merger | Mallinckrodt | Other cash consideration | Subsequent Event
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Payments to Acquire Businesses, Gross		0.0
Mallinckrodt & Endo Merger | Mallinckrodt | Payment to Endo stockholders | Subsequent Event
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Payments to Acquire Businesses, Gross		100,000,000.0
Mallinckrodt & Endo Merger | Mallinckrodt | Other merger consideration attributable to Endo stock-based awards | Subsequent Event
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Payments to Acquire Businesses, Gross		7,100,000
Mallinckrodt & Endo Merger | Mallinckrodt | Obligation to cash settle shares underlying certain Endo stock-based awards | Subsequent Event
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Payments to Acquire Businesses, Gross		$ 2,400,000
Mallinckrodt & Endo Merger | Endo | Subsequent Event
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Shares, Issued | shares		76,313,462
Business Combination Exchange ratio		0.2575
Payments to Acquire Businesses, Gross		$ 1.31

[1] Represents legal, financial, and other advisory and consulting expenses, which primarily relate to shareholder matters, integration planning, and regulatory costs associated with the Business Combination. Refer to Note 3 for further information on the Business Combination.

[2] Represents costs primarily related to the Separation during the three and six months ended June 27, 2025 and professional fees incurred as the Company explored potential sales of non-core assets to enable further deleveraging post-emergence from the 2023 Bankruptcy Proceedings during the three and six months ended June 28, 2024.