Mallinckrodt (MNKTQ) 10-K 26 Mar 24 2023 FY Annual report Financial data

Document And Entity Information

Document And Entity Information [Abstract] - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 29, 2023	Mar. 22, 2024	Jun. 30, 2023
Document and Entity Information [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 29, 2023
Document Transition Report	false
Entity File Number	001-35803
Entity Registrant Name	Mallinckrodt plc
Entity Incorporation, State or Country Code	L2
Entity Tax Identification Number	98-1088325
Entity Central Index Key	0001567892
Current Fiscal Year End Date	--12-29
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	FY
Amendment Flag	false
Entity Address, Address Line One	College Business & Technology Park
Entity Address, Address Line Two	Cruiserath
Entity Address, Address Line Three	Blanchardstown
Entity Address, City or Town	Dublin
Entity Address, Postal Zip Code	15
Entity Address, Country	IE
Country Region	353
City Area Code	1
Local Phone Number	696 0000
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Public Float			$ 15.3
Share Price			$ 1.18
Entity Common Stock, Shares Outstanding		19,696,335
ICFR Auditor Attestation Flag	true
Auditor Firm ID	34
Auditor Name	Deloitte & Touche LLP
Auditor Location	St. Louis, Missouri
Title of 12(b) Security	Ordinary shares, par value $0.01 per share
Financial Designation, Predecessor and Successor	Successor
Document Financial Statement Error Correction [Flag]	false

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) shares in Millions, $ in Millions	1 Months Ended	6 Months Ended		11 Months Ended	12 Months Ended
	Dec. 29, 2023	Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 31, 2021
Income Statement [Abstract]
Net sales	$ 243	$ 1,039.7	$ 874.6	$ 1,622.9	$ 2,208.8
Cost of sales	179.1	991	582	1,300.5	1,317.1
Gross profit	63.9	48.7	292.6	322.4	891.7
Selling, general and administrative expenses	64.2	268.9	266.3	448.2	581.4
Research and development expenses	15.9	64.2	65.5	97.1	205.2
Restructuring charges, net	0	11.1	9.6	0.9	26.9
Non-restructuring impairment charges	2.6	0	0	135.9	154.9
Opioid-Related Litigation Settlement loss	0	0	0	0	125
Operating loss	(20.2)	(316.7)	(57.8)	(517.4)	(202.9)
Interest expense	(28.3)	(324.3)	(108.6)	(507.2)	(222.6)
Interest income	0.9	3.9	0.6	14.7	1.9
Other income (expense), net	5.4	10	(14.6)	(6.5)	22
Reorganization items, net	(4)	(23.2)	(630.9)	(892.7)	(428.2)
Loss from continuing operations before income taxes	(46.2)	(650.3)	(811.3)	(1,909.1)	(829.8)
Benefit from income taxes	(8)	(52)	(497.3)	(277.8)	(106.3)
Loss from continuing operations	(38.2)	(598.3)	(314)	(1,631.3)	(723.5)
Income from discontinued operations, net of tax benefit of $—, $—, $—, $—, and $(5.0)	0	0.2	0.9	0	6.1
Net loss	$ (38.2)	$ (598.1)	$ (313.1)	$ (1,631.3)	$ (717.4)
Loss from continuing operations	$ (1.94)	$ (45.43)	$ (3.70)	$ (122.75)	$ (8.54)
Income from discontinued operations	0	0.02	0.01	0	0.07
Earnings Per Share, Basic	$ (1.94)	$ (45.41)	$ (3.69)	$ (122.75)	$ (8.47)
Basic weighted-average shares outstanding	19.7	13.2	84.8	13.3	84.7
Loss from continuing operations	$ (1.94)	$ (45.43)	$ (3.70)	$ (122.75)	$ (8.54)
Income from discontinued operations	0	0.02	0.01	0	0.07
Earnings Per Share, Diluted	$ (1.94)	$ (45.41)	$ (3.69)	$ (122.75)	$ (8.47)
Weighted Average Number of Shares Outstanding, Diluted	19.7	13.2	84.8	13.3	84.7
Basic loss per share (Note 8):
Loss from continuing operations	$ (1.94)	$ (45.43)	$ (3.70)	$ (122.75)	$ (8.54)
Income from discontinued operations	$ 0	$ 0.02	$ 0.01	$ 0	$ 0.07
Basic weighted-average shares outstanding	19.7	13.2	84.8	13.3	84.7
Diluted loss per share (Note 8):
Loss from continuing operations	$ (1.94)	$ (45.43)	$ (3.70)	$ (122.75)	$ (8.54)
Income from discontinued operations	0	0.02	0.01	0	0.07
Net loss	$ (1.94)	$ (45.41)	$ (3.69)	$ (122.75)	$ (8.47)
Diluted weighted-average shares outstanding	19.7	13.2	84.8	13.3	84.7

Consolidated Statements of Op_2

Consolidated Statements of Operations (Parenthetical) - USD ($) shares in Millions, $ in Millions	1 Months Ended	6 Months Ended		11 Months Ended	12 Months Ended
	Dec. 29, 2023	Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 31, 2021
Income Statement [Abstract]
Discontinued Operation, Tax Effect of Discontinued Operation	$ 0	$ 0	$ 0	$ 0	$ (5)
Liabilities management and separation costs	1.4	21.2	9	157.7	1.2
Reorganization items, net	$ (4)	$ (23.2)	$ (630.9)	$ (892.7)	$ (428.2)
Loss from continuing operations	$ (1.94)	$ (45.43)	$ (3.70)	$ (122.75)	$ (8.54)
Income from discontinued operations	0	0.02	0.01	0	0.07
Earnings Per Share, Basic	$ (1.94)	$ (45.41)	$ (3.69)	$ (122.75)	$ (8.47)
Basic weighted-average shares outstanding	19.7	13.2	84.8	13.3	84.7
Loss from continuing operations	$ (1.94)	$ (45.43)	$ (3.70)	$ (122.75)	$ (8.54)
Income from discontinued operations	0	0.02	0.01	0	0.07
Earnings Per Share, Diluted	$ (1.94)	$ (45.41)	$ (3.69)	$ (122.75)	$ (8.47)
Weighted Average Number of Shares Outstanding, Diluted	19.7	13.2	84.8	13.3	84.7
Net sales	$ 243	$ 1,039.7	$ 874.6	$ 1,622.9	$ 2,208.8
Cost of sales	179.1	991	582	1,300.5	1,317.1
Gross profit	63.9	48.7	292.6	322.4	891.7
Selling, general and administrative expenses	64.2	268.9	266.3	448.2	581.4
Research and development expenses	15.9	64.2	65.5	97.1	205.2
Restructuring charges, net	0	11.1	9.6	0.9	26.9
Non-restructuring impairment charges	2.6	0	0	135.9	154.9
Opioid-Related Litigation Settlement loss	0	0	0	0	125
Operating Income (Loss)	(20.2)	(316.7)	(57.8)	(517.4)	(202.9)
Interest expense	(28.3)	(324.3)	(108.6)	(507.2)	(222.6)
Interest income	0.9	3.9	0.6	14.7	1.9
Other income (expense), net	5.4	10	(14.6)	(6.5)	22
Loss from continuing operations before income taxes	(46.2)	(650.3)	(811.3)	(1,909.1)	(829.8)
Benefit from income taxes	(8)	(52)	(497.3)	(277.8)	(106.3)
Income (loss) from continuing operations	(38.2)	(598.3)	(314)	(1,631.3)	(723.5)
Income (loss) from discontinued operations, net of income taxes	0	0.2	0.9	0	6.1
Net loss	$ (38.2)	$ (598.1)	$ (313.1)	$ (1,631.3)	$ (717.4)

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Operations - USD ($) $ in Millions	1 Months Ended	6 Months Ended		11 Months Ended	12 Months Ended
	Dec. 29, 2023	Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 31, 2021
Currency translation adjustments	$ 5.2	$ 2.1	$ (1.5)	$ (5.3)	$ (0.5)
Net loss	(38.2)	(598.1)	(313.1)	(1,631.3)	(717.4)
Unrecognized loss on derivatives	0	0	0	5.7	0
Unrecognized (loss) gain on benefit plans	(1.6)	8.7	0	(0.8)	1.8
Total other comprehensive income (loss), net of tax	3.6	10.8	(1.5)	(0.4)	1.3
Comprehensive loss	(34.6)	(587.3)	(314.6)	(1,631.7)	(716.1)
Other comprehensive income (loss), net of tax
Currency translation adjustments	5.2	2.1	(1.5)	(5.3)	(0.5)
Unrecognized (loss) gain on benefit plans	(1.6)	8.7	0	(0.8)	1.8
Unrecognized loss on derivatives	0	0	0	5.7	0
Total other comprehensive income (loss), net of tax	3.6	10.8	(1.5)	(0.4)	1.3
Comprehensive loss	(34.6)	(587.3)	(314.6)	(1,631.7)	(716.1)
Retained Earnings
Net loss	$ (38.2)	$ (598.1)	$ (313.1)	$ (1,631.3)	$ (717.4)

Consolidated Balance Sheets

Consolidated Balance Sheets $ in Millions	Dec. 29, 2023 USD ($) $ / shares shares	Dec. 30, 2022 USD ($) $ / shares shares
Current Assets:
Cash and cash equivalents	$ 262.7	$ 409.5
Accounts receivable, less allowance for doubtful accounts of $6.5 and $4.4	377.5	405.3
Inventories	982.7	947.6
Prepaid expenses and other current assets	138.9	273.4
Total current assets	1,761.8	2,035.8
Property, plant and equipment, net	321.7	457.6
Intangible assets, net	608.4	2,843.8
Deferred income taxes	801	475.5
Other assets	240.7	201.1
Total Assets	3,733.6	6,013.8
Current Liabilities:
Current maturities of long-term debt	6.5	44.1
Accounts payable	100.4	114
Accrued payroll and payroll-related costs	82.8	49.5
Accrued interest	20.1	29
Acthar Gel-Related Settlement liability	21.5	16.5
Opioid-Related Litigation Settlement liability	0	200
Accrued and other current liabilities	269.9	290.7
Total current liabilities	501.2	743.8
Long-term debt	1,755.9	3,027.7
Acthar Gel-Related Settlement liability	128.5	75
Opioid-Related Litigation Settlement liability	0	379.9
Pension and postretirement benefits	40.6	41
Environmental liabilities	35.1	35.8
Deferred income taxes	0	0.3
Other income tax liabilities	19.6	18.2
Other liabilities	92.5	78.7
Total Liabilities	2,573.4	$ 4,400.1
Preferred shares, shares outstanding (in shares) | shares		0
Preferred shares, shares issued (in shares) | shares		0
Preferred shares, shares authorized (in shares) | shares		500,000,000
Preferred shares, par value (in usd per share) | $ / shares		$ 0.01
Shareholders' Equity:
Additional paid-in capital	1,194.6	$ 2,191
Retained deficit	(38.2)	(588.2)
Accumulated other comprehensive income	3.6	10.8
Total Shareholders' Equity	1,160.2	1,613.7
Total Liabilities and Shareholders' Equity	$ 3,733.6	$ 6,013.8
Ordinary A shares, shares authorized (in shares) | shares	25,000	40,000
Ordinary A shares, shares issued (in shares) | shares	0	0
Ordinary A shares, shares outstanding (in shares) | shares	0	0
Ordinary shares, shares authorized (in shares) | shares	500,000,000	500,000,000
Predecessor Reorganization
Current Liabilities:
Preferred shares, shares outstanding (in shares) | shares		0
Preferred shares, shares issued (in shares) | shares		0
Preferred shares, shares authorized (in shares) | shares		500,000,000
Preferred shares, par value (in usd per share) | $ / shares		$ 0.20
Shareholders' Equity:
Preferred Stock, Value, Outstanding	$ 0	$ 0
Common Stock, Other Value, Outstanding	0	0
Common Stock, Value, Outstanding	$ 0	$ 0.1
Ordinary shares, shares authorized (in shares) | shares		500,000,000
Successor
Current Liabilities:
Preferred shares, shares outstanding (in shares) | shares	0
Preferred shares, shares issued (in shares) | shares	0
Preferred shares, shares authorized (in shares) | shares	500,000,000
Preferred shares, par value (in usd per share) | $ / shares	$ 0.01
Shareholders' Equity:
Common Stock, Other Value, Outstanding	$ 0	$ 0
Common Stock, Value, Outstanding	$ 0.2	$ 0
Ordinary shares, shares authorized (in shares) | shares	500,000,000

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) $ in Millions	Dec. 29, 2023 USD ($) $ / shares shares	Dec. 29, 2023 € / shares	Nov. 14, 2023 $ / shares shares	Dec. 30, 2022 USD ($) $ / shares shares	Dec. 30, 2022 € / shares
Accounts Receivable, Allowance for Credit Loss, Current | $	$ 6.5			$ 4.4
Preferred shares, par value (in usd per share) | $ / shares				$ 0.01
Preferred shares, shares authorized (in shares)				500,000,000
Preferred shares, shares issued (in shares)				0
Preferred shares, shares outstanding (in shares)				0
Treasury Stock, Common, Shares	0			0
Ordinary A shares, par value (in eur per share) | € / shares		€ 1			€ 1
Ordinary A shares, shares authorized (in shares)	25,000			40,000
Ordinary A shares, shares issued (in shares)	0			0
Ordinary A shares, shares outstanding (in shares)	0			0
Ordinary shares, par value (in usd per share) | $ / shares	$ 0.01			$ 0.01
Ordinary shares, shares authorized (in shares)	500,000,000			500,000,000
Successor
Preferred shares, par value (in usd per share) | $ / shares	$ 0.01
Preferred shares, shares authorized (in shares)	500,000,000
Preferred shares, shares issued (in shares)	0
Preferred shares, shares outstanding (in shares)	0
Ordinary shares, shares authorized (in shares)	500,000,000
Ordinary shares, shares issued (in shares)			19,696,335
Ordinary shares, shares outstanding (in shares)	19,696,335		19,696,335
Predecessor Reorganization
Preferred shares, par value (in usd per share) | $ / shares				$ 0.20
Preferred shares, shares authorized (in shares)				500,000,000
Preferred shares, shares issued (in shares)				0
Preferred shares, shares outstanding (in shares)				0
Ordinary shares, par value (in usd per share) | $ / shares			$ 0.01	$ 0.20
Ordinary shares, shares authorized (in shares)				500,000,000
Ordinary shares, shares issued (in shares)				13,170,932
Ordinary shares, shares outstanding (in shares)				13,170,932
Common Class A | Successor
Ordinary shares, par value (in usd per share) | $ / shares	$ 1
Ordinary shares, shares authorized (in shares)	40,000
Ordinary shares, shares issued (in shares)	0
Ordinary shares, shares outstanding (in shares)	0
Common Class A | Predecessor Reorganization
Ordinary shares, par value (in usd per share) | $ / shares				$ 1
Ordinary shares, shares authorized (in shares)				40,000
Ordinary shares, shares issued (in shares)				0
Ordinary shares, shares outstanding (in shares)				0

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Millions	1 Months Ended	6 Months Ended		11 Months Ended	12 Months Ended
	Dec. 29, 2023	Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 31, 2021
Restricted Cash and Investments, Current	$ 40.8	$ 20.6	$ 113	$ 47	$ 24
Restricted Cash and Investments, Noncurrent	39.9	36.6	36.4	39.7	36.2
Cash and cash equivalents	262.7	409.5	297.9	186.7	1,345
Cash and Cash Equivalents, Including Restricted Cash	343.4	466.7	447.3	273.4	1,405.2
Effect of currency rate changes on cash	1.4	(1.1)	(3.9)	(1.7)	(1.9)
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect	70	19.4	(957.9)	(193.3)	278.2
Cash Flows from Operating Activities:
Net loss	(38.2)	(598.1)	(313.1)	(1,631.3)	(717.4)
Adjustments to reconcile net cash provided by operating activities:
Depreciation and amortization	25.8	347.5	321.8	490.3	675.8
Share-based compensation	0	1.4	1.7	8.9	10.2
Deferred income taxes	(6.6)	(24.9)	(473)	(319.2)	(59.9)
Non-cash impairment charges	3.8	0	0	179.9	154.9
Losses on divestiture	0	0	0	0	0.8
Other non-cash items	6.7	16.8	35.3	14.2	(1.6)
Reorganization items, net	0	0	425.4	831	22.5
Accretion Expense	(0.7)	(139.2)	0	(176.7)	0
Changes in assets and liabilities:
Accounts receivable, net	88.6	(18.1)	49.8	(65.5)	98.2
Inventories	51.1	267.9	(33.2)	108.2	(14)
Accounts payable	25.8	8.1	(3.6)	(37.2)	(1.1)
Increase (Decrease) in Accrued Consulting	(6.8)	(90.7)	0.1	25	14.3
Income taxes	(1.7)	(30.1)	(26.9)	169.3	108.5
Opioid-Related Litigation Settlement liability	0	0	0	(250)	125
Increase (Decrease) Acthar Gel-Related Litigation Settlement	0	0	0	(16.5)	0
Medicaid lawsuit	0	0	0	0	(4.2)
Payment of claims	0	0	(629)	0	0
Other	30.6	28.1	2.4	(95.9)	43.4
Net cash from operating activities	178.4	47.1	(642.3)	(412.1)	455.4
Cash Flows from Investing Activities:
Capital expenditures	(8.5)	(28.8)	(33.4)	(53.9)	(55.3)
Proceeds related to divestiture, net of cash	0	70	0	0	15.7
Other	0.9	(13.7)	0.4	1.2	1.8
Net cash from investing activities	(7.6)	27.5	(33)	(52.7)	(37.8)
Cash Flows from Financing Activities:
Issuance of external debt	0	0	650	380	0
Repayment of external debt	(102.2)	(50.1)	(904.6)	(102.6)	(137.5)
Debt financing costs	0	0	(24.1)	(4.1)	0
Other	0	(4)	0	(0.1)	0
Net Cash Provided by (Used in) Financing Activities	(102.2)	(54.1)	(278.7)	273.2	(137.5)
Supplemental Disclosures of Cash Flow Information:
Cash paid for interest, net	9	164.1	111.5	316.8	243.2
Cash paid (received) for income taxes, net	$ 0.3	$ 3	$ 3	$ (128)	$ (160)

Consolidated Statement of Chang

Consolidated Statement of Changes in Shareholders' Equity Statement - USD ($) $ in Millions	Total	Ordinary Shares	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive (Loss) Income	Treasury Stock, Common
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other Comprehensive Income (Loss), Net of Tax	$ 1.3				$ 1.3
Beginning balance, shares at Dec. 25, 2020		94,100,000				9,500,000
Beginning balance, value at Dec. 25, 2020	1,019.2	$ 18.8	$ 5,587.6	$ (2,961.5)	(9.6)	$ (1,616.1)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(717.4)			(717.4)
Vesting of restricted shares, shares		200,000				100,000
Vesting of restricted shares, value	(0.1)	$ (0.1)	0			$ 0
Share-based compensation	10.2		10.2
Ending balance, shares at Dec. 31, 2021		94,300,000				9,600,000
Ending balance, value at Dec. 31, 2021	313.4	$ 18.9	5,597.8	(3,678.9)	(8.3)	$ (1,616.1)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other Comprehensive Income (Loss), Net of Tax	(1.5)				(1.5)
Net loss	(313.1)			(313.1)
Share-based compensation	1.7		1.7
Cancellation of Predecessor equity	(0.5)	(18.9)	(5,599.5)	3,992	9.8	1,616.1
Cancellation of Predecessor equity, Shares		$ (94.3)				$ (9.6)
Ending balance, shares at Jun. 16, 2022		13,200,000				0
Ending balance, value at Jun. 16, 2022	2,203.6	$ 0.1	2,203.5	0	0	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock Issued During Period, Shares, New Issues		13,200,000
Stock Issued During Period, Value, New Issues	2,189.7	$ 0.1	2,189.6
Adjustments to Additional Paid in Capital, Warrant Issued	13.9		13.9
Other Comprehensive Income (Loss), Net of Tax	10.8				10.8
Net loss	(598.1)			(598.1)
Share-based compensation	1.4		1.4
Ending balance, shares at Dec. 30, 2022		13,200,000				0
Ending balance, value at Dec. 30, 2022	1,613.7	$ 0.1	2,191	(588.2)	10.8	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Payments for Repurchase of Warrants	(4)		13.9	(9.9)
Other Comprehensive Income (Loss), Net of Tax	(0.4)				(0.4)
Net loss	(1,631.3)			(1,631.3)
Vesting of restricted shares, shares		300,000				100,000
Vesting of restricted shares, value	0.1	$ 0	0			$ 0.1
Share-based compensation	8.9		8.9
Cancellation of Predecessor equity	9.2	(0.1)	(2,199.9)	2,219.5	(10.4)	0.1
Cancellation of Predecessor equity, Shares		$ (13.5)				$ (0.1)
Ending balance, shares at Nov. 14, 2023		19,700,000				0
Ending balance, value at Nov. 14, 2023	1,194.8	$ 0.2	1,194.6	0	0	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock Issued During Period, Shares, New Issues		19,700,000
Stock Issued During Period, Value, New Issues	1,169.7	$ 0.2	1,169.5
Adjustments to Additional Paid in Capital, Contingent Value Rights Issued			25.1
Adjustments to Additional Paid in Capital, Warrant Issued	25.1
Beginning balance, shares at Dec. 30, 2022		13,200,000				0
Beginning balance, value at Dec. 30, 2022	1,613.7	$ 0.1	2,191	(588.2)	10.8	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Vesting of restricted shares, value						$ 0
Ending balance, shares at Dec. 29, 2023		19,700,000				0
Ending balance, value at Dec. 29, 2023	1,160.2	$ 0.2	1,194.6	(38.2)	3.6	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other Comprehensive Income (Loss), Net of Tax	3.6
Beginning balance, shares at Nov. 14, 2023		19,700,000				0
Beginning balance, value at Nov. 14, 2023	1,194.8	$ 0.2	1,194.6	0	0	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(38.2)			(38.2)
Ending balance, shares at Dec. 29, 2023		19,700,000				0
Ending balance, value at Dec. 29, 2023	$ 1,160.2	$ 0.2	$ 1,194.6	$ (38.2)	$ 3.6	$ 0

Reorganizations

Reorganizations	12 Months Ended
	Dec. 29, 2023
Reorganizations [Abstract]
Reorganization under Chapter 11 of US Bankruptcy Code Disclosure [Text Block]	2. Emergence from Voluntary Reorganization During the pendency of the 2023 and 2020 Bankruptcy Proceedings, the Company and each of the respective debtors and debtors in-possession in the 2023 Chapter 11 Cases ("2023 Debtors") and the 2020 Chapter 11 Cases ("2020 Debtors") operated their businesses as debtors-in-possession under the jurisdiction of the Bankruptcy Court and in accordance with the applicable provisions of the Bankruptcy Code and orders of the Bankruptcy Court. As debtors-in-possession, the 2023 and 2020 Debtors were authorized to continue to operate as ongoing businesses, and were allowed to pay all debts and honor all obligations arising in the ordinary course of their businesses after the respective 2023 and 2020 Petition Dates. However, the 2023 and 2020 Debtors were not allowed to pay third-party claims or creditors on account of obligations arising before the respective 2023 or 2020 Petition Dates or engage in transactions outside the ordinary course of business without approval of the Bankruptcy Court. Under the Bankruptcy Code, third-party actions to collect pre-petition indebtedness owed by the 2023 and 2020 Debtors, as well as most litigation pending against the Company as of the 2023 and 2020 Petition Dates, were subject to an automatic stay. See " Plan of Reorganization" below for the distributions to creditors and interest holders. Plan of Reorganization 2023 Plan In accordance with the 2023 Plan, the following significant transactions occurred upon the Company's emergence from the 2023 Bankruptcy Proceedings on the 2023 Effective Date: • DIP Claims (as defined below) were converted on a dollar-for-dollar basis into First-Out Takeback Term Loans (as defined below); • Pre-petition first lien term debt was reduced from $2,861.8 million to $1,650.0 million, which was in the form of Takeback Debt (as defined below) distributed to post-petition term lenders and pre-petition first lien creditors; • The pre-petition first lien creditors also received 92.3% of the 2023 Debtors’ reorganized equity (subject to dilution from equity reserved under the management incentive program ("MIP") and the Opioid CVRs (as defined below) if equity settled), plus cash in an amount sufficient to repay in full accrued and unpaid interest on the pre-petition first lien debt, and Second-Out Takeback Debt (as defined below); • Pre-petition second lien debt was eliminated in its entirety, with pre-petition second lien creditors receiving 7.7% of the 2023 Debtors’ reorganized equity (subject to dilution from equity reserved under the MIP and the Opioid CVRs, if equity settled); • The 2023 Debtors’ remaining opioid-related litigation settlement payment obligations (including the $200.0 million installment payment originally due on June 16, 2023) were permanently eliminated, subject to the Company (a) making a $250.0 million payment to the Opioid Master Disbursement Trust II ("Trust") prior to the commencement of the 2023 Chapter 11 Cases (which was made on August 24, 2023) and (b) entering into the CVR Agreement (as defined below); • The 2023 Debtors’ non-monetary obligations to the Trust were generally preserved, including the compliance-related operating injunction; • All other claims against the 2023 Debtors (with the exception of subordinated securities claims) were treated as unimpaired, including the Debtors’ settlement under the 2020 Plan with governmental entities regarding Acthar ® Gel (repository corticotropin injection) ("Acthar Gel"), and the associated Corporate Integrity Agreement, and also trade liabilities; and • All of Mallinckrodt ordinary shares were cancelled for no consideration. Contingent Value Right Agreement On the 2023 Effective Date and pursuant to the 2023 Plan, the Company entered into a contingent value right agreement ("CVR Agreement") with the Trust. Pursuant to the terms of the CVR Agreement, the Company issued 1,036,649 contingent value rights ("Opioid CVRs") to the Trust, which Opioid CVRs entitle the Trust to receive from the Company, when exercised, an amount in cash equal to (a) the Market Price (as defined in the CVR Agreement) of one new ordinary share of the Company (subject to adjustment as described in the CVR Agreement) at the time of exercise less (b) $99.36 (subject to adjustment as described in the CVR Agreement) ("Cash Payment"), subject to the right of the Company to, at its option but subject to certain conditions, issue new ordinary shares to the Trust in lieu of making some or all of the Cash Payment due upon exercise in accordance with the terms of the CVR Agreement. The Opioid CVRs are exercisable at any time for four years after the 2023 Effective Date. Upon entering into the CVR Agreement the terms of the final amendment to the opioid-related litigation settlement ("Opioid-Related Litigation Settlement") obligation agreement ("Opioid Deferred Cash Payment Agreement") and the Company's prior obligation to pay all remaining Opioid-Related Litigation Settlement payment obligations ("Opioid Deferred Cash Payment") were permanently eliminated. For further discussion of the Opioid-Related Litigation Settlement, refer to Note 18. Registration Rights Agreement On the 2023 Effective Date and pursuant to the 2023 Plan, the Company entered into a registration rights agreement ("Registration Rights Agreement") with certain owners of new ordinary shares (any owner of new ordinary shares, a "Company Shareholder"). Pursuant to the terms of the Registration Rights Agreement, following an initial public offering, any Company Shareholder that owns 1% or more of the new ordinary shares (calculated in accordance with the Registration Rights Agreement) shall have customary "piggyback" registration rights. In addition, 180 days following an initial public offering, any Company Shareholder owning at least 15% of the new ordinary shares (calculated in accordance with the Registration Rights Agreement) shall have the right to initiate up to three (3) demand registrations each, subject to customary exceptions. Information Rights Deed On the 2023 Effective Date and pursuant to the 2023 Plan, the Company entered into a deed poll ("Information Rights Deed") for the benefit of each Company Shareholder that (i) has executed and delivered to the Company a confidentiality agreement substantially in the form appended thereto (each, a "Confidentiality Agreement") and (ii) is not a person designated on the list of Company competitors maintained by the Board (such Company Shareholder, an "Information Rights Holder"). Pursuant to the terms of the Information Rights Deed, the Company will provide each Information Rights Holder with (i) quarterly unaudited financial statements within 60 days following each quarter’s end and (ii) annual audited financial statements within 120 days following each fiscal year’s end (together, the "Financial Statements"). Upon the written request of an Information Rights Holder, the Company will also provide a copy of the register of members of the Company then in effect, regular updates on any process initiated under Article 43 of the Company’s new articles of association as well as any such additional information that an Information Rights Holder may reasonably request as required for regulatory, tax or compliance purposes. In addition, the Company will schedule a teleconference with all Information Rights Holders between five (5) and twenty (20) business days after the delivery of each Financial Statement to discuss the Company’s business, financial condition and financial performance, prospects, liquidity and capital resources. The foregoing information rights are subject to customary exceptions. New Takeback Debt On the 2023 Effective Date and pursuant to the 2023 Plan, Mallinckrodt International Finance S.A. ("MIFSA") and Mallinckrodt CB LLC ("MCB" and, together with MIFSA, the "Issuers"), each of which is a subsidiary of the Company, (i) entered into a new senior secured first lien term loan facility with an aggregate principal amount of approximately $871.4 million ("Takeback Term Loans"), consisting of approximately $229.4 million of "first-out" Takeback Term Loans ("First-Out Takeback Term Loans") and approximately $642.0 million of "second-out" Takeback Term Loans ("Second-Out Takeback Term Loans") and (ii) issued approximately $778.6 million in aggregate principal amount of "second-out" 14.75% senior secured first lien notes due 2028 ("Takeback Notes") and, together with the Second-Out Takeback Term Loans, the "Second-Out Takeback Debt" and, together with the Takeback Term Loans, the "Takeback Debt"). All allowed claims ("DIP Claims") under the Senior Secured Debtor-In-Possession Credit Agreement, dated as of September 8, 2023 ("DIP Credit Agreement"), by and among the Company, MIFSA and MCB, as debtors and debtors-in-possession, the lenders from time to time party thereto, Acquiom Agency Services LLC and Seaport Loan Products LLC, as co-administrative agents, and Acquiom Agency Services LLC, as collateral agent, not otherwise satisfied in cash were converted on a dollar-for-dollar basis into First-Out Takeback Term Loans. Each holder of an allowed claim related to the outstanding 10.00% first lien senior secured notes due 2025 issued by certain of the Company’s subsidiaries ("2025 First Lien Notes") pursuant to the indenture, dated as of April 7, 2020, the outstanding 11.50% first lien senior secured notes due 2028 issued by certain of the Company’s subsidiaries ("2028 First Lien Notes" and, together with the 2025 First Lien Notes, the "First Lien Notes") pursuant to the indenture, dated as of June 16, 2022, or the first lien senior secured term loans due 2027 borrowed by certain of the Company’s subsidiaries pursuant to the credit agreement, dated as of June 16, 2022, by and among the Company, certain of its subsidiaries and the lenders party thereto, Acquiom Agency Services LLC and Seaport Loan Products LLC, as co-administrative agents, and Deutsche Bank AG New York Branch, as collateral agent ("First Lien Term Loans" and, collectively with the First Lien Notes , the "First Lien Debt"), elected to receive such Takeback Debt either in the form of Second-Out Takeback Term Loans or Takeback Notes. 2020 Plan In accordance with the effectuated 2020 Plan, the following significant transactions occurred upon the Company's emergence from the 2020 Bankruptcy Proceedings on the 2020 Effective Date: Resolution of Opioid-Related Claims . Pursuant to the 2020 Plan and the 2020 Scheme of Arrangement, all previous opioid claims against the Company and its subsidiaries were deemed to have been settled, discharged, waived, released and extinguished in full, and the Company and its subsidiaries ceased to have any liability or obligation with respect to such claims, which were treated in accordance with the 2020 Plan as follows: ◦ Opioid claims were channeled to certain trusts, which were to receive $1,725.0 million in deferred payments from the Company and certain of its subsidiaries consisting of (i) a $450.0 million payment upon the 2020 Effective Date (of which $2.6 million was prefunded); (ii) a $200.0 million payment upon each of the first and second anniversaries of the 2020 Effective Date; (iii) a $150.0 million payment upon each of the third through seventh anniversaries of the 2020 Effective Date; and (iv) a $125.0 million payment upon the eighth anniversary of the 2020 Effective Date (collectively, the "Opioid Deferred Payments") with the Company retaining an eighteen-month option to prepay outstanding Opioid Deferred Payments (other than the initial 2020 Effective Date payment) at a discount (and to prepay the Opioid Deferred Payments at their undiscounted value even after the expiration of such eighteen-month period). The Opioid Deferred Payments were unsecured and were guaranteed by Mallinckrodt and its subsidiaries that were borrowers, issuers or guarantors under the First Lien Term Loans, the 2028 First Lien Notes, the 2025 First Lien Notes, the 2025 Second Lien Notes (as defined below) and the 2029 Second Lien Notes (as defined below), and certain future indebtedness (subject to certain exceptions). The Opioid Deferred Cash Payments Agreement contained affirmative and negative covenants (including an obligation to offer to pay the Opioid Deferred Payments without discount upon the occurrence of certain change of control triggering events) and events of default (subject in certain cases to customary grace and cure periods). The occurrence of an event of default under the Opioid Deferred Cash Payments Agreement could result in the required repayment of all outstanding Opioid Deferred Payments and could cause a cross-default that could result in the acceleration of certain indebtedness of Mallinckrodt and its subsidiaries. The Opioid Deferred Cash Payments Agreement was subsequently permanently eliminated as discussed above in " 2023 Plan ." • Opioid claimants also received, in addition to other potential consideration, 3,290,675 warrants for approximately 19.99% of the Predecessor's new ordinary shares, with a nominal value $0.01 per share, after giving effect to the exercise of the warrants, but subject to dilution from equity reserved under the management incentive plan, exercisable at any time on or prior to the sixth anniversary of the 2020 Effective Date, at a strike price of $103.40 per ordinary share ("Opioid Warrants"). These Opioid Warrants were subsequently repurchased during the period June 17, 2022 through December 30, 2022 (Predecessor) for $4.0 million. • Pursuant to the 2020 Plan, certain subsidiaries of the Company remained subject to an agreed-upon operating injunction with respect to the operation of their opioid business. The Company reaffirmed the obligations contained in the operating injunction in connection with the 2023 Bankruptcy Proceedings. Governmental Acthar Gel-Related Settlement Pursuant to the 2020 Plan and the 2020 Scheme of Arrangement, on the 2020 Effective Date, all claims of the U.S. Department of Justice ("DOJ") and other governmental parties relating to Acthar Gel against the Company were deemed to have been settled, discharged, waived, released and extinguished in full, and the Company ceased to have any liability or obligation with respect to such claims, which were treated in accordance with the 2020 Plan and the terms of the settlement as summarized below: • The Company entered into an agreement with the DOJ and other governmental parties to settle a range of litigation matters and disputes relating to Acthar Gel ("Acthar Gel-Related Settlement") including a Medicaid lawsuit with the Centers for Medicare and Medicaid Services ("CMS"), a related False Claims Act ("FCA") lawsuit in Boston, and an Eastern District of Pennsylvania ("EDPA") FCA lawsuit principally relating to interactions of Acthar Gel's previous owner (Questcor Pharmaceuticals Inc.) with an independent charitable foundation. To implement the Acthar Gel-Related Settlement, the Company entered into two settlement agreements with the U.S. and certain relators. Under the Acthar Gel-Related Settlement, which was conditioned upon the Company commencing its 2020 Chapter 11 Cases and provided for the distributions the applicable claimants received under the 2020 Plan, the Company agreed to pay $260.0 million to the DOJ and other parties over seven years and reset Acthar Gel’s Medicaid rebate calculation as of July 1, 2020, such that state Medicaid programs would receive 100% rebates on Acthar Gel Medicaid sales, based on then-current Acthar Gel pricing. The $260.0 million in payments consists of (i) a $15.0 million payment upon the 2020 Effective Date; (ii) a $15.0 million payment upon the first anniversary of the 2020 Effective Date; (iii) a $20.0 million payment upon each of the second and third anniversaries of the 2020 Effective Date; (iv) a $32.5 million payment upon each of the fourth and fifth anniversaries of the 2020 Effective Date; and (v) a $62.5 million payment upon the sixth and seventh anniversaries of the 2020 Effective Date. Also in connection with the Acthar Gel-Related Settlement, the Company entered into (a) separate settlement agreements with certain states, the Commonwealth of Puerto Rico, the District of Columbia and the above-noted relators, which further implement the Acthar Gel-Related Settlement, and (b) a five-year corporate integrity agreement with the Office of Inspector General of the U.S. Department of Health and Human Services ("HHS") in March 2022. As a result of these agreements, upon effectiveness of the Acthar Gel-Related Settlement in connection with the effectiveness of the 2020 Plan, the U.S. Government dropped its demand for approximately $640 million in retrospective Medicaid rebates for Acthar Gel and agreed to dismiss the FCA lawsuit in Boston and the EDPA FCA lawsuit. Similarly, state and territory Attorneys General also dropped related lawsuits. In turn, the Company dismissed its appeal of the U.S. District Court for the District of Columbia's adverse decision in the Medicaid lawsuit, which was filed in the U.S. Court of Appeals for the District of Columbia Circuit. • Mallinckrodt entered into the Acthar Gel-Related Settlement with the DOJ and other governmental parties solely to move past these litigation matters and disputes and does not make any admission of liability or wrongdoing. • In accordance with the effectuated Acthar Gel-Related Settlement, on June 28, 2022, the Bankruptcy Court entered an order dismissing the federal government's FCA lawsuit with prejudice, and further ordered the related state lawsuits dismissed without prejudice. • In accordance with the effectuated Acthar Gel-Related Settlement, on July 20, 2022, the court entered an order dismissing the EDPA FCA lawsuit with prejudice. • As of December 29, 2023 (Successor), the Company has $236.1 million of remaining obligation with respect to the Acthar Gel-Related Litigation Settlement. Satisfaction of Predecessor Term Loans and Repayment of Existing Revolver On the 2020 Effective Date and pursuant to the 2020 Plan, the Issuers, each of which is a subsidiary of the Company, entered into a facility governing the First Lien Term Loans consisting of $1,392.9 million aggregate principal amount of 2017 replacement term loans ("2017 Replacement Term Loans") and $369.7 million aggregate principal amount of 2018 replacement term loans ("2018 Replacement Term Loans"). Pursuant to the 2020 Plan and the 2020 Scheme of Arrangement, on the 2020 Effective Date, lenders holding allowed claims in respect of the predecessor senior secured term loans due September 2024 ("2024 Term Loans") and predecessor senior secured term loans due February 2025 ("2025 Term Loans" and, together with the 2024 Term Loans, the "Predecessor Term Loans") incurred by the Issuers received their pro rata share of the 2017 Replacement Term Loans (in the case of the 2024 Term Loans) or the 2018 Replacement Term Loans (in the case of the 2025 Term Loans) and payment in cash of an exit fee equal to 1.00% of the remaining principal amount of Predecessor Term Loans held by such lenders in satisfaction thereof. Pursuant to the 2020 Plan and the 2020 Scheme of Arrangement, on the 2020 Effective Date, lenders’ allowed claims in respect of the existing $900.0 million senior secured revolving credit facility ("Predecessor Revolver") incurred by the Issuers and certain of their respective subsidiaries were paid in full in cash. Reinstatement of 2025 First Lien Notes Pursuant to the 2020 Plan and the 2020 Scheme of Arrangement, on the 2020 Effective Date, the Issuers’ existing 2025 First Lien Notes in an aggregate principal amount of $495.0 million and the note documents relating thereto were reinstated. In addition, pursuant to the terms of the indenture governing the 2025 First Lien Notes, the Issuers, Mallinckrodt plc and the subsidiary guarantors of the 2025 First Lien Notes entered into a supplemental indenture, dated as of the 2020 Effective Date, pursuant to which certain additional assets were added to the collateral securing the 2025 First Lien Notes and the guarantees thereof. Satisfaction of 10.00% Second Lien Senior Secured Notes due 2025 Pursuant to the 2020 Plan and the 2020 Scheme of Arrangement, on the 2020 Effective Date, lenders holding allowed claims in respect of the Issuers’ existing 10.00% second lien senior secured notes due 2025 ("Predecessor 2025 Second Lien Notes") in an aggregate principal amount of $322.9 million received their pro rata share of a like aggregate principal amount of new 10.00% second lien senior secured notes due 2025 ("2025 Second Lien Notes") in satisfaction thereof. Discharge of Mallinckrodt's Guaranteed Unsecured Notes Pursuant to the 2020 Plan and the 2020 Scheme of Arrangement, on the 2020 Effective Date, holders of allowed claims in respect of the Issuers' 5.75% senior notes due 2022, the 5.625% senior notes due 2023 and the 5.50% senior notes due 2025 ("Predecessor Guaranteed Unsecured Notes") received their pro rata share of $375.0 million aggregate principal amount of new 10.00% second lien senior secured notes due 2029 ("2029 Second Lien Notes" and together with the 2025 Second Lien Notes, the "Second Lien Notes") and 100% of the new 13,170,932 ordinary shares issued on the 2020 Effective Date, subject to dilution by the Opioid Warrants described above and the management incentive plan. Otherwise, pursuant to the 2020 Plan and the 2020 Scheme of Arrangement, all claims in respect of the Predecessor Guaranteed Unsecured Notes and the indentures governing them were settled, discharged, waived, released and extinguished in full. Resolution of Other Remaining Claims Pursuant to the 2020 Plan and the 2020 Scheme of Arrangement, on the 2020 Effective Date, certain trade claims and other general unsecured claims, including the claims of holders of the predecessor 4.75% senior notes due April 2023, against the 2020 Debtors were deemed to have been settled, discharged, waived, released and extinguished in full, and Mallinckrodt ceased to have any liability or obligation with respect to such claims, which were then treated in accordance with the 2020 Plan and the 2020 Scheme of Arrangement, which provided for the holders of such claims to share in $135.0 million in cash, plus other potential consideration, including but not limited to 35.0% of the proceeds of the sale of the StrataGraft ® (allogenic cultured keratinocytes and dermal fibroblasts in murine collagen - dsat) ("StrataGraft") Priority Review Voucher ("PRV") and $20.0 million payable upon the achievement of (1) U.S. Food and Drug Administration ("FDA") approval of Terlivaz ® (terlipressin) ("Terlivaz") and (2) cumulative net sales of $100.0 million of Terlivaz. On June 30, 2022, subsequent to the 2020 Effective Date, the Company completed the sale of its PRV for $100.0 million and received net proceeds of $65.0 million as the buyer remitted the remaining $35.0 million to the General Unsecured Claims Trustee pursuant to the terms of (i) the 2020 Plan, and (ii) that certain General Unsecured Claims Trust Agreement entered into in connection with the 2020 Plan. New Warrant Agreement and Warrant Termination Agreement Pursuant to the 2020 Plan and the 2020 Scheme of Arrangement, on the 2020 Effective Date, Mallinckrodt entered into a warrant agreement and issued 3,290,675 Opioid Warrants to purchase ordinary shares to MNK Opioid Abatement Fund, LLC ("Initial Holder"), a wholly owned subsidiary of the Trust, a master disbursement trust established in accordance with the 2020 Plan. Each Opioid Warrant was initially exercisable for one ordinary share at an initial exercise price of $103.40 per ordinary share, subject to the cashless exercise provisions contained in the warrant agreement. The Opioid Warrants were exercisable from the date of issuance until the sixth anniversary of the 2020 Effective Date. The warrant agreement governing the Opioid Warrants contained customary anti-dilution adjustments in the event of any share dividends, share splits, distributions, issuance of additional shares or options, or certain other dilutive events. On December 8, 2022, the Company, the Initial Holder and the Trust entered into an agreement to accelerate the expiration date of the Opioid Warrants and to terminate the warrant agreement in exchange for a payment by the Company of $4.0 million to the Initial Holder (" Warrant Termination Agreement" ). At the closing of the transactions contemplated by the Warrant Termination Agreement, which also occurred on December 8, 2022, the Company and the warrant agent entered into an amendment to the warrant agreement that accelerated the expiration of the Opioid Warrants to such date. As a result of such expiration, the Opioid Warrants were cancelled and each of the warrant agreement and the registration rights agreement that were entered into on the 2020 Effective Date terminated in accordance with its terms. Exit Financing On the 2020 Effective Date, the Company issued $650.0 million aggregate principal amount of 2028 First Lien Notes and entered into a receivables financing facility based on a borrowing base with a maximum draw of up to $200.0 million. Predecessor Chapter 11 Financing The Company obtained an order of the Bankruptcy Court in the 2020 Chapter 11 Cases (in a form agreed with, among others, the agent under the predecessor senior secured credit facilities, lenders under the Predecessor Revolver and the Predecessor Term Loans and holders of the 2025 First Lien Notes and the Predecessor 2025 Second Lien Notes) permitting the use of cash collateral to finance the 2020 Chapter 11 Cases. Such order required that the Company make cash adequate protection payments on the Predecessor Revolver and Predecessor Term Loans for, among other things, unpaid pre-petition and post-petition fees, unpaid pre-petition interest (at the specified contract rate) and post-petition interest (at a rate equal to (1) the adjusted London Interbank Offered Rate ("LIBOR"), plus (2) the contract-specified applicable margin, and plus (3) an incremental 200 basis points), quarterly amortization payments on the Predecessor Term Loans and reimbursement of certain costs. Such order further required that the Company make cash adequate protection payments on the 2025 First Lien Notes and the Predecessor 2025 Second Lien Notes for, among other things, unpaid pre-petition and post-petition interest (at the specified non-default interest rate) and reimbursement of certain costs. On April 13, 2021, the 2020 Debtors received Bankruptcy Court approval of their motion to amend the final cash collateral order as of March 22, 2021 to pay post-petition interest on the Predecessor Term Loans at a rate equal to (1) the adjusted LIBOR, plus (2) the contract-specified applicable margin, and plus (3) an incremental 250 basis points for its Predecessor Term Loans. The cash collateral order expired on June 16, 2022 (Predecessor). Interest expense incurred and paid with respect to the incremental adequate protection payments of 200 basis points and 250 basis points on the Predecessor Revolver and the Predecessor Term Loans, respectively, were as follows: Predecessor Period from Year Ended December 31, 2021 Interest expense incurred for adequate protection payments $ 28.8 $ 63.1 Cash paid for adequate protection payments 28.8 66.7 Contractual interest While the 2023 Chapter 11 Cases were pending, the Company was not accruing interest on the Second Lien Notes as of the 2023 Petition Date on a go-forward basis as the 2023 Debtors did not anticipate making interest payments due under the Second Lien Notes. The total aggregate amount of interest payments contractually due under the predecessor Second Lien Notes for the period from December 31, 2022 to November 14, 2023 (Predecessor), which the Company did not pay, was $48.5 million. The 2023 Debtors paid all interest payments in full as they came due under the predecessor First Lien Debt. While the 2020 Chapter 11 Cases were pending, the Company was not accruing interest on its predecessor unsecured debt instruments as of the 2020 Petition Date on a go-forward basis as the 2020 Debtors did not anticipate making interest payments due under their respective predecessor unsecured debt instruments; however, the 2020 Debtors expected to pay all interest payments in full as they came due under their respective predecessor senior secured debt instruments. The total aggregate amount of interest payments contractually due under the Company's predecessor unsecured debt instruments, which the Company did not pay as the obligation was extinguished pursuant to the 2020 Plan, was $46.5 million and $93.0 million for the period January 1, 2022 through June 16, 2022 (Predecessor) and fiscal 2021 (Predecessor), respectively. 3. Fresh-start Accounting 2023 Fresh-Start Accounting The Company qualified for and adopted fresh-start accounting as of the 2023 Effective Date in accordance with ASC 852 as (i) the reorganization value of the assets of the Company immediately prior to the date of effectuation of the 2023 Plan was less than the post-petition liabilities and allowed claims and (ii) the holders of the voting shares of the Predecessor immediately before effectuation of the 2023 Plan received less than 50% of the voting shares of the Successor. Reorganization Value Reorganization value represents the fair value of the Successor's total assets and is intended to approximate the amount a willing buyer would pay for the assets immediately after restructuring. Upon the application of fresh-start accounting, the Company allocated the reorganization value to its identified tangible and intangible assets and liabilities based on their estimated fair values in accordance with ASC Topic 805 - Business Combinations . Deferred income tax amounts were determined in accordance with ASC Topic 740 - Income Taxes . As set forth in the disclosure statement approved by the Bankruptcy Court, the enterprise value of the Successor was estimated to be between $2,700.0 million and $3,200.0 million, with a midpoint of $2,950.0 million, which was estimated with the assistance of third-party valuation advisors using various valuation methods, including (i) discounted cash flow analysis, a calculation of the present value of the future cash flows to be generated by the business based on its projection, and (ii) comparable public company analysis, a method to estimate the value of a company relative to other publicly traded companies with similar operation and financial characteristics. The estimated enterprise value per the disclosure statement included estimated equity value in a range between $1,110.0 million and $1,610.0 million, with a midpoint of $1,360.0 million. The basis of the discounted cash flow analysis used in developing the enterprise value was based on Company prepared projections that included a variety of estimates and assumptions. While the Company considers such estimates and assumptions reasonable, they are inherently subject to significant business, economic and competitive uncertainties, many of which are beyond the Company’s control and, therefore, may not be realized. Changes in these estimates and assumptions may have had a significant effect on the determination of the Company’s enterprise value. The following table reconciles the enterprise value to the implied fair value of the Successor's equity as of the 2023 Effective Date: Enterprise value $ 2,950.0 Plus: Non-operating assets, net (1) 290.0 Less: Fair value of debt (1,882.7) Less: Fair value of Acthar Gel-Related Settlement and Terlivaz contingent value rights (162.5) Successor equity value $ 1,194.8 (1) Represents non-operating assets and liabilities which were excluded from the enterprise value as put forth in the disclosure statement as there were no cash projections associated with these net assets. Upon the application of fresh-start accounting, the Company allocated the reorganization value to its individual assets based on their estimated fair values. Reorganization value represents the fair value of the Successor’s assets before considering liabilities. The following table reconciles the Company's enterprise value to its reorganization value as of the 2023 Effective Date: Enterprise value $ 2,950.0 Plus: Non-operating assets, net 290.0 Plus: Current liabilities (excluding debt or debt-like items) (1) 404.8 Plus: Other non-current liabilities (excluding debt or debt-like items) (2) 172.1 Reorganization value of Successor assets $ 3,816.9 (1) Excludes $7.6 million related to the current portion of the embedded derivative. (2) Excludes $15.0 million

Fresh-Start Accounting

Fresh-Start Accounting	12 Months Ended
	Dec. 29, 2023
Reorganizations [Abstract]
Fresh-Start Accounting	2. Emergence from Voluntary Reorganization During the pendency of the 2023 and 2020 Bankruptcy Proceedings, the Company and each of the respective debtors and debtors in-possession in the 2023 Chapter 11 Cases ("2023 Debtors") and the 2020 Chapter 11 Cases ("2020 Debtors") operated their businesses as debtors-in-possession under the jurisdiction of the Bankruptcy Court and in accordance with the applicable provisions of the Bankruptcy Code and orders of the Bankruptcy Court. As debtors-in-possession, the 2023 and 2020 Debtors were authorized to continue to operate as ongoing businesses, and were allowed to pay all debts and honor all obligations arising in the ordinary course of their businesses after the respective 2023 and 2020 Petition Dates. However, the 2023 and 2020 Debtors were not allowed to pay third-party claims or creditors on account of obligations arising before the respective 2023 or 2020 Petition Dates or engage in transactions outside the ordinary course of business without approval of the Bankruptcy Court. Under the Bankruptcy Code, third-party actions to collect pre-petition indebtedness owed by the 2023 and 2020 Debtors, as well as most litigation pending against the Company as of the 2023 and 2020 Petition Dates, were subject to an automatic stay. See " Plan of Reorganization" below for the distributions to creditors and interest holders. Plan of Reorganization 2023 Plan In accordance with the 2023 Plan, the following significant transactions occurred upon the Company's emergence from the 2023 Bankruptcy Proceedings on the 2023 Effective Date: • DIP Claims (as defined below) were converted on a dollar-for-dollar basis into First-Out Takeback Term Loans (as defined below); • Pre-petition first lien term debt was reduced from $2,861.8 million to $1,650.0 million, which was in the form of Takeback Debt (as defined below) distributed to post-petition term lenders and pre-petition first lien creditors; • The pre-petition first lien creditors also received 92.3% of the 2023 Debtors’ reorganized equity (subject to dilution from equity reserved under the management incentive program ("MIP") and the Opioid CVRs (as defined below) if equity settled), plus cash in an amount sufficient to repay in full accrued and unpaid interest on the pre-petition first lien debt, and Second-Out Takeback Debt (as defined below); • Pre-petition second lien debt was eliminated in its entirety, with pre-petition second lien creditors receiving 7.7% of the 2023 Debtors’ reorganized equity (subject to dilution from equity reserved under the MIP and the Opioid CVRs, if equity settled); • The 2023 Debtors’ remaining opioid-related litigation settlement payment obligations (including the $200.0 million installment payment originally due on June 16, 2023) were permanently eliminated, subject to the Company (a) making a $250.0 million payment to the Opioid Master Disbursement Trust II ("Trust") prior to the commencement of the 2023 Chapter 11 Cases (which was made on August 24, 2023) and (b) entering into the CVR Agreement (as defined below); • The 2023 Debtors’ non-monetary obligations to the Trust were generally preserved, including the compliance-related operating injunction; • All other claims against the 2023 Debtors (with the exception of subordinated securities claims) were treated as unimpaired, including the Debtors’ settlement under the 2020 Plan with governmental entities regarding Acthar ® Gel (repository corticotropin injection) ("Acthar Gel"), and the associated Corporate Integrity Agreement, and also trade liabilities; and • All of Mallinckrodt ordinary shares were cancelled for no consideration. Contingent Value Right Agreement On the 2023 Effective Date and pursuant to the 2023 Plan, the Company entered into a contingent value right agreement ("CVR Agreement") with the Trust. Pursuant to the terms of the CVR Agreement, the Company issued 1,036,649 contingent value rights ("Opioid CVRs") to the Trust, which Opioid CVRs entitle the Trust to receive from the Company, when exercised, an amount in cash equal to (a) the Market Price (as defined in the CVR Agreement) of one new ordinary share of the Company (subject to adjustment as described in the CVR Agreement) at the time of exercise less (b) $99.36 (subject to adjustment as described in the CVR Agreement) ("Cash Payment"), subject to the right of the Company to, at its option but subject to certain conditions, issue new ordinary shares to the Trust in lieu of making some or all of the Cash Payment due upon exercise in accordance with the terms of the CVR Agreement. The Opioid CVRs are exercisable at any time for four years after the 2023 Effective Date. Upon entering into the CVR Agreement the terms of the final amendment to the opioid-related litigation settlement ("Opioid-Related Litigation Settlement") obligation agreement ("Opioid Deferred Cash Payment Agreement") and the Company's prior obligation to pay all remaining Opioid-Related Litigation Settlement payment obligations ("Opioid Deferred Cash Payment") were permanently eliminated. For further discussion of the Opioid-Related Litigation Settlement, refer to Note 18. Registration Rights Agreement On the 2023 Effective Date and pursuant to the 2023 Plan, the Company entered into a registration rights agreement ("Registration Rights Agreement") with certain owners of new ordinary shares (any owner of new ordinary shares, a "Company Shareholder"). Pursuant to the terms of the Registration Rights Agreement, following an initial public offering, any Company Shareholder that owns 1% or more of the new ordinary shares (calculated in accordance with the Registration Rights Agreement) shall have customary "piggyback" registration rights. In addition, 180 days following an initial public offering, any Company Shareholder owning at least 15% of the new ordinary shares (calculated in accordance with the Registration Rights Agreement) shall have the right to initiate up to three (3) demand registrations each, subject to customary exceptions. Information Rights Deed On the 2023 Effective Date and pursuant to the 2023 Plan, the Company entered into a deed poll ("Information Rights Deed") for the benefit of each Company Shareholder that (i) has executed and delivered to the Company a confidentiality agreement substantially in the form appended thereto (each, a "Confidentiality Agreement") and (ii) is not a person designated on the list of Company competitors maintained by the Board (such Company Shareholder, an "Information Rights Holder"). Pursuant to the terms of the Information Rights Deed, the Company will provide each Information Rights Holder with (i) quarterly unaudited financial statements within 60 days following each quarter’s end and (ii) annual audited financial statements within 120 days following each fiscal year’s end (together, the "Financial Statements"). Upon the written request of an Information Rights Holder, the Company will also provide a copy of the register of members of the Company then in effect, regular updates on any process initiated under Article 43 of the Company’s new articles of association as well as any such additional information that an Information Rights Holder may reasonably request as required for regulatory, tax or compliance purposes. In addition, the Company will schedule a teleconference with all Information Rights Holders between five (5) and twenty (20) business days after the delivery of each Financial Statement to discuss the Company’s business, financial condition and financial performance, prospects, liquidity and capital resources. The foregoing information rights are subject to customary exceptions. New Takeback Debt On the 2023 Effective Date and pursuant to the 2023 Plan, Mallinckrodt International Finance S.A. ("MIFSA") and Mallinckrodt CB LLC ("MCB" and, together with MIFSA, the "Issuers"), each of which is a subsidiary of the Company, (i) entered into a new senior secured first lien term loan facility with an aggregate principal amount of approximately $871.4 million ("Takeback Term Loans"), consisting of approximately $229.4 million of "first-out" Takeback Term Loans ("First-Out Takeback Term Loans") and approximately $642.0 million of "second-out" Takeback Term Loans ("Second-Out Takeback Term Loans") and (ii) issued approximately $778.6 million in aggregate principal amount of "second-out" 14.75% senior secured first lien notes due 2028 ("Takeback Notes") and, together with the Second-Out Takeback Term Loans, the "Second-Out Takeback Debt" and, together with the Takeback Term Loans, the "Takeback Debt"). All allowed claims ("DIP Claims") under the Senior Secured Debtor-In-Possession Credit Agreement, dated as of September 8, 2023 ("DIP Credit Agreement"), by and among the Company, MIFSA and MCB, as debtors and debtors-in-possession, the lenders from time to time party thereto, Acquiom Agency Services LLC and Seaport Loan Products LLC, as co-administrative agents, and Acquiom Agency Services LLC, as collateral agent, not otherwise satisfied in cash were converted on a dollar-for-dollar basis into First-Out Takeback Term Loans. Each holder of an allowed claim related to the outstanding 10.00% first lien senior secured notes due 2025 issued by certain of the Company’s subsidiaries ("2025 First Lien Notes") pursuant to the indenture, dated as of April 7, 2020, the outstanding 11.50% first lien senior secured notes due 2028 issued by certain of the Company’s subsidiaries ("2028 First Lien Notes" and, together with the 2025 First Lien Notes, the "First Lien Notes") pursuant to the indenture, dated as of June 16, 2022, or the first lien senior secured term loans due 2027 borrowed by certain of the Company’s subsidiaries pursuant to the credit agreement, dated as of June 16, 2022, by and among the Company, certain of its subsidiaries and the lenders party thereto, Acquiom Agency Services LLC and Seaport Loan Products LLC, as co-administrative agents, and Deutsche Bank AG New York Branch, as collateral agent ("First Lien Term Loans" and, collectively with the First Lien Notes , the "First Lien Debt"), elected to receive such Takeback Debt either in the form of Second-Out Takeback Term Loans or Takeback Notes. 2020 Plan In accordance with the effectuated 2020 Plan, the following significant transactions occurred upon the Company's emergence from the 2020 Bankruptcy Proceedings on the 2020 Effective Date: Resolution of Opioid-Related Claims . Pursuant to the 2020 Plan and the 2020 Scheme of Arrangement, all previous opioid claims against the Company and its subsidiaries were deemed to have been settled, discharged, waived, released and extinguished in full, and the Company and its subsidiaries ceased to have any liability or obligation with respect to such claims, which were treated in accordance with the 2020 Plan as follows: ◦ Opioid claims were channeled to certain trusts, which were to receive $1,725.0 million in deferred payments from the Company and certain of its subsidiaries consisting of (i) a $450.0 million payment upon the 2020 Effective Date (of which $2.6 million was prefunded); (ii) a $200.0 million payment upon each of the first and second anniversaries of the 2020 Effective Date; (iii) a $150.0 million payment upon each of the third through seventh anniversaries of the 2020 Effective Date; and (iv) a $125.0 million payment upon the eighth anniversary of the 2020 Effective Date (collectively, the "Opioid Deferred Payments") with the Company retaining an eighteen-month option to prepay outstanding Opioid Deferred Payments (other than the initial 2020 Effective Date payment) at a discount (and to prepay the Opioid Deferred Payments at their undiscounted value even after the expiration of such eighteen-month period). The Opioid Deferred Payments were unsecured and were guaranteed by Mallinckrodt and its subsidiaries that were borrowers, issuers or guarantors under the First Lien Term Loans, the 2028 First Lien Notes, the 2025 First Lien Notes, the 2025 Second Lien Notes (as defined below) and the 2029 Second Lien Notes (as defined below), and certain future indebtedness (subject to certain exceptions). The Opioid Deferred Cash Payments Agreement contained affirmative and negative covenants (including an obligation to offer to pay the Opioid Deferred Payments without discount upon the occurrence of certain change of control triggering events) and events of default (subject in certain cases to customary grace and cure periods). The occurrence of an event of default under the Opioid Deferred Cash Payments Agreement could result in the required repayment of all outstanding Opioid Deferred Payments and could cause a cross-default that could result in the acceleration of certain indebtedness of Mallinckrodt and its subsidiaries. The Opioid Deferred Cash Payments Agreement was subsequently permanently eliminated as discussed above in " 2023 Plan ." • Opioid claimants also received, in addition to other potential consideration, 3,290,675 warrants for approximately 19.99% of the Predecessor's new ordinary shares, with a nominal value $0.01 per share, after giving effect to the exercise of the warrants, but subject to dilution from equity reserved under the management incentive plan, exercisable at any time on or prior to the sixth anniversary of the 2020 Effective Date, at a strike price of $103.40 per ordinary share ("Opioid Warrants"). These Opioid Warrants were subsequently repurchased during the period June 17, 2022 through December 30, 2022 (Predecessor) for $4.0 million. • Pursuant to the 2020 Plan, certain subsidiaries of the Company remained subject to an agreed-upon operating injunction with respect to the operation of their opioid business. The Company reaffirmed the obligations contained in the operating injunction in connection with the 2023 Bankruptcy Proceedings. Governmental Acthar Gel-Related Settlement Pursuant to the 2020 Plan and the 2020 Scheme of Arrangement, on the 2020 Effective Date, all claims of the U.S. Department of Justice ("DOJ") and other governmental parties relating to Acthar Gel against the Company were deemed to have been settled, discharged, waived, released and extinguished in full, and the Company ceased to have any liability or obligation with respect to such claims, which were treated in accordance with the 2020 Plan and the terms of the settlement as summarized below: • The Company entered into an agreement with the DOJ and other governmental parties to settle a range of litigation matters and disputes relating to Acthar Gel ("Acthar Gel-Related Settlement") including a Medicaid lawsuit with the Centers for Medicare and Medicaid Services ("CMS"), a related False Claims Act ("FCA") lawsuit in Boston, and an Eastern District of Pennsylvania ("EDPA") FCA lawsuit principally relating to interactions of Acthar Gel's previous owner (Questcor Pharmaceuticals Inc.) with an independent charitable foundation. To implement the Acthar Gel-Related Settlement, the Company entered into two settlement agreements with the U.S. and certain relators. Under the Acthar Gel-Related Settlement, which was conditioned upon the Company commencing its 2020 Chapter 11 Cases and provided for the distributions the applicable claimants received under the 2020 Plan, the Company agreed to pay $260.0 million to the DOJ and other parties over seven years and reset Acthar Gel’s Medicaid rebate calculation as of July 1, 2020, such that state Medicaid programs would receive 100% rebates on Acthar Gel Medicaid sales, based on then-current Acthar Gel pricing. The $260.0 million in payments consists of (i) a $15.0 million payment upon the 2020 Effective Date; (ii) a $15.0 million payment upon the first anniversary of the 2020 Effective Date; (iii) a $20.0 million payment upon each of the second and third anniversaries of the 2020 Effective Date; (iv) a $32.5 million payment upon each of the fourth and fifth anniversaries of the 2020 Effective Date; and (v) a $62.5 million payment upon the sixth and seventh anniversaries of the 2020 Effective Date. Also in connection with the Acthar Gel-Related Settlement, the Company entered into (a) separate settlement agreements with certain states, the Commonwealth of Puerto Rico, the District of Columbia and the above-noted relators, which further implement the Acthar Gel-Related Settlement, and (b) a five-year corporate integrity agreement with the Office of Inspector General of the U.S. Department of Health and Human Services ("HHS") in March 2022. As a result of these agreements, upon effectiveness of the Acthar Gel-Related Settlement in connection with the effectiveness of the 2020 Plan, the U.S. Government dropped its demand for approximately $640 million in retrospective Medicaid rebates for Acthar Gel and agreed to dismiss the FCA lawsuit in Boston and the EDPA FCA lawsuit. Similarly, state and territory Attorneys General also dropped related lawsuits. In turn, the Company dismissed its appeal of the U.S. District Court for the District of Columbia's adverse decision in the Medicaid lawsuit, which was filed in the U.S. Court of Appeals for the District of Columbia Circuit. • Mallinckrodt entered into the Acthar Gel-Related Settlement with the DOJ and other governmental parties solely to move past these litigation matters and disputes and does not make any admission of liability or wrongdoing. • In accordance with the effectuated Acthar Gel-Related Settlement, on June 28, 2022, the Bankruptcy Court entered an order dismissing the federal government's FCA lawsuit with prejudice, and further ordered the related state lawsuits dismissed without prejudice. • In accordance with the effectuated Acthar Gel-Related Settlement, on July 20, 2022, the court entered an order dismissing the EDPA FCA lawsuit with prejudice. • As of December 29, 2023 (Successor), the Company has $236.1 million of remaining obligation with respect to the Acthar Gel-Related Litigation Settlement. Satisfaction of Predecessor Term Loans and Repayment of Existing Revolver On the 2020 Effective Date and pursuant to the 2020 Plan, the Issuers, each of which is a subsidiary of the Company, entered into a facility governing the First Lien Term Loans consisting of $1,392.9 million aggregate principal amount of 2017 replacement term loans ("2017 Replacement Term Loans") and $369.7 million aggregate principal amount of 2018 replacement term loans ("2018 Replacement Term Loans"). Pursuant to the 2020 Plan and the 2020 Scheme of Arrangement, on the 2020 Effective Date, lenders holding allowed claims in respect of the predecessor senior secured term loans due September 2024 ("2024 Term Loans") and predecessor senior secured term loans due February 2025 ("2025 Term Loans" and, together with the 2024 Term Loans, the "Predecessor Term Loans") incurred by the Issuers received their pro rata share of the 2017 Replacement Term Loans (in the case of the 2024 Term Loans) or the 2018 Replacement Term Loans (in the case of the 2025 Term Loans) and payment in cash of an exit fee equal to 1.00% of the remaining principal amount of Predecessor Term Loans held by such lenders in satisfaction thereof. Pursuant to the 2020 Plan and the 2020 Scheme of Arrangement, on the 2020 Effective Date, lenders’ allowed claims in respect of the existing $900.0 million senior secured revolving credit facility ("Predecessor Revolver") incurred by the Issuers and certain of their respective subsidiaries were paid in full in cash. Reinstatement of 2025 First Lien Notes Pursuant to the 2020 Plan and the 2020 Scheme of Arrangement, on the 2020 Effective Date, the Issuers’ existing 2025 First Lien Notes in an aggregate principal amount of $495.0 million and the note documents relating thereto were reinstated. In addition, pursuant to the terms of the indenture governing the 2025 First Lien Notes, the Issuers, Mallinckrodt plc and the subsidiary guarantors of the 2025 First Lien Notes entered into a supplemental indenture, dated as of the 2020 Effective Date, pursuant to which certain additional assets were added to the collateral securing the 2025 First Lien Notes and the guarantees thereof. Satisfaction of 10.00% Second Lien Senior Secured Notes due 2025 Pursuant to the 2020 Plan and the 2020 Scheme of Arrangement, on the 2020 Effective Date, lenders holding allowed claims in respect of the Issuers’ existing 10.00% second lien senior secured notes due 2025 ("Predecessor 2025 Second Lien Notes") in an aggregate principal amount of $322.9 million received their pro rata share of a like aggregate principal amount of new 10.00% second lien senior secured notes due 2025 ("2025 Second Lien Notes") in satisfaction thereof. Discharge of Mallinckrodt's Guaranteed Unsecured Notes Pursuant to the 2020 Plan and the 2020 Scheme of Arrangement, on the 2020 Effective Date, holders of allowed claims in respect of the Issuers' 5.75% senior notes due 2022, the 5.625% senior notes due 2023 and the 5.50% senior notes due 2025 ("Predecessor Guaranteed Unsecured Notes") received their pro rata share of $375.0 million aggregate principal amount of new 10.00% second lien senior secured notes due 2029 ("2029 Second Lien Notes" and together with the 2025 Second Lien Notes, the "Second Lien Notes") and 100% of the new 13,170,932 ordinary shares issued on the 2020 Effective Date, subject to dilution by the Opioid Warrants described above and the management incentive plan. Otherwise, pursuant to the 2020 Plan and the 2020 Scheme of Arrangement, all claims in respect of the Predecessor Guaranteed Unsecured Notes and the indentures governing them were settled, discharged, waived, released and extinguished in full. Resolution of Other Remaining Claims Pursuant to the 2020 Plan and the 2020 Scheme of Arrangement, on the 2020 Effective Date, certain trade claims and other general unsecured claims, including the claims of holders of the predecessor 4.75% senior notes due April 2023, against the 2020 Debtors were deemed to have been settled, discharged, waived, released and extinguished in full, and Mallinckrodt ceased to have any liability or obligation with respect to such claims, which were then treated in accordance with the 2020 Plan and the 2020 Scheme of Arrangement, which provided for the holders of such claims to share in $135.0 million in cash, plus other potential consideration, including but not limited to 35.0% of the proceeds of the sale of the StrataGraft ® (allogenic cultured keratinocytes and dermal fibroblasts in murine collagen - dsat) ("StrataGraft") Priority Review Voucher ("PRV") and $20.0 million payable upon the achievement of (1) U.S. Food and Drug Administration ("FDA") approval of Terlivaz ® (terlipressin) ("Terlivaz") and (2) cumulative net sales of $100.0 million of Terlivaz. On June 30, 2022, subsequent to the 2020 Effective Date, the Company completed the sale of its PRV for $100.0 million and received net proceeds of $65.0 million as the buyer remitted the remaining $35.0 million to the General Unsecured Claims Trustee pursuant to the terms of (i) the 2020 Plan, and (ii) that certain General Unsecured Claims Trust Agreement entered into in connection with the 2020 Plan. New Warrant Agreement and Warrant Termination Agreement Pursuant to the 2020 Plan and the 2020 Scheme of Arrangement, on the 2020 Effective Date, Mallinckrodt entered into a warrant agreement and issued 3,290,675 Opioid Warrants to purchase ordinary shares to MNK Opioid Abatement Fund, LLC ("Initial Holder"), a wholly owned subsidiary of the Trust, a master disbursement trust established in accordance with the 2020 Plan. Each Opioid Warrant was initially exercisable for one ordinary share at an initial exercise price of $103.40 per ordinary share, subject to the cashless exercise provisions contained in the warrant agreement. The Opioid Warrants were exercisable from the date of issuance until the sixth anniversary of the 2020 Effective Date. The warrant agreement governing the Opioid Warrants contained customary anti-dilution adjustments in the event of any share dividends, share splits, distributions, issuance of additional shares or options, or certain other dilutive events. On December 8, 2022, the Company, the Initial Holder and the Trust entered into an agreement to accelerate the expiration date of the Opioid Warrants and to terminate the warrant agreement in exchange for a payment by the Company of $4.0 million to the Initial Holder (" Warrant Termination Agreement" ). At the closing of the transactions contemplated by the Warrant Termination Agreement, which also occurred on December 8, 2022, the Company and the warrant agent entered into an amendment to the warrant agreement that accelerated the expiration of the Opioid Warrants to such date. As a result of such expiration, the Opioid Warrants were cancelled and each of the warrant agreement and the registration rights agreement that were entered into on the 2020 Effective Date terminated in accordance with its terms. Exit Financing On the 2020 Effective Date, the Company issued $650.0 million aggregate principal amount of 2028 First Lien Notes and entered into a receivables financing facility based on a borrowing base with a maximum draw of up to $200.0 million. Predecessor Chapter 11 Financing The Company obtained an order of the Bankruptcy Court in the 2020 Chapter 11 Cases (in a form agreed with, among others, the agent under the predecessor senior secured credit facilities, lenders under the Predecessor Revolver and the Predecessor Term Loans and holders of the 2025 First Lien Notes and the Predecessor 2025 Second Lien Notes) permitting the use of cash collateral to finance the 2020 Chapter 11 Cases. Such order required that the Company make cash adequate protection payments on the Predecessor Revolver and Predecessor Term Loans for, among other things, unpaid pre-petition and post-petition fees, unpaid pre-petition interest (at the specified contract rate) and post-petition interest (at a rate equal to (1) the adjusted London Interbank Offered Rate ("LIBOR"), plus (2) the contract-specified applicable margin, and plus (3) an incremental 200 basis points), quarterly amortization payments on the Predecessor Term Loans and reimbursement of certain costs. Such order further required that the Company make cash adequate protection payments on the 2025 First Lien Notes and the Predecessor 2025 Second Lien Notes for, among other things, unpaid pre-petition and post-petition interest (at the specified non-default interest rate) and reimbursement of certain costs. On April 13, 2021, the 2020 Debtors received Bankruptcy Court approval of their motion to amend the final cash collateral order as of March 22, 2021 to pay post-petition interest on the Predecessor Term Loans at a rate equal to (1) the adjusted LIBOR, plus (2) the contract-specified applicable margin, and plus (3) an incremental 250 basis points for its Predecessor Term Loans. The cash collateral order expired on June 16, 2022 (Predecessor). Interest expense incurred and paid with respect to the incremental adequate protection payments of 200 basis points and 250 basis points on the Predecessor Revolver and the Predecessor Term Loans, respectively, were as follows: Predecessor Period from Year Ended December 31, 2021 Interest expense incurred for adequate protection payments $ 28.8 $ 63.1 Cash paid for adequate protection payments 28.8 66.7 Contractual interest While the 2023 Chapter 11 Cases were pending, the Company was not accruing interest on the Second Lien Notes as of the 2023 Petition Date on a go-forward basis as the 2023 Debtors did not anticipate making interest payments due under the Second Lien Notes. The total aggregate amount of interest payments contractually due under the predecessor Second Lien Notes for the period from December 31, 2022 to November 14, 2023 (Predecessor), which the Company did not pay, was $48.5 million. The 2023 Debtors paid all interest payments in full as they came due under the predecessor First Lien Debt. While the 2020 Chapter 11 Cases were pending, the Company was not accruing interest on its predecessor unsecured debt instruments as of the 2020 Petition Date on a go-forward basis as the 2020 Debtors did not anticipate making interest payments due under their respective predecessor unsecured debt instruments; however, the 2020 Debtors expected to pay all interest payments in full as they came due under their respective predecessor senior secured debt instruments. The total aggregate amount of interest payments contractually due under the Company's predecessor unsecured debt instruments, which the Company did not pay as the obligation was extinguished pursuant to the 2020 Plan, was $46.5 million and $93.0 million for the period January 1, 2022 through June 16, 2022 (Predecessor) and fiscal 2021 (Predecessor), respectively. 3. Fresh-start Accounting 2023 Fresh-Start Accounting The Company qualified for and adopted fresh-start accounting as of the 2023 Effective Date in accordance with ASC 852 as (i) the reorganization value of the assets of the Company immediately prior to the date of effectuation of the 2023 Plan was less than the post-petition liabilities and allowed claims and (ii) the holders of the voting shares of the Predecessor immediately before effectuation of the 2023 Plan received less than 50% of the voting shares of the Successor. Reorganization Value Reorganization value represents the fair value of the Successor's total assets and is intended to approximate the amount a willing buyer would pay for the assets immediately after restructuring. Upon the application of fresh-start accounting, the Company allocated the reorganization value to its identified tangible and intangible assets and liabilities based on their estimated fair values in accordance with ASC Topic 805 - Business Combinations . Deferred income tax amounts were determined in accordance with ASC Topic 740 - Income Taxes . As set forth in the disclosure statement approved by the Bankruptcy Court, the enterprise value of the Successor was estimated to be between $2,700.0 million and $3,200.0 million, with a midpoint of $2,950.0 million, which was estimated with the assistance of third-party valuation advisors using various valuation methods, including (i) discounted cash flow analysis, a calculation of the present value of the future cash flows to be generated by the business based on its projection, and (ii) comparable public company analysis, a method to estimate the value of a company relative to other publicly traded companies with similar operation and financial characteristics. The estimated enterprise value per the disclosure statement included estimated equity value in a range between $1,110.0 million and $1,610.0 million, with a midpoint of $1,360.0 million. The basis of the discounted cash flow analysis used in developing the enterprise value was based on Company prepared projections that included a variety of estimates and assumptions. While the Company considers such estimates and assumptions reasonable, they are inherently subject to significant business, economic and competitive uncertainties, many of which are beyond the Company’s control and, therefore, may not be realized. Changes in these estimates and assumptions may have had a significant effect on the determination of the Company’s enterprise value. The following table reconciles the enterprise value to the implied fair value of the Successor's equity as of the 2023 Effective Date: Enterprise value $ 2,950.0 Plus: Non-operating assets, net (1) 290.0 Less: Fair value of debt (1,882.7) Less: Fair value of Acthar Gel-Related Settlement and Terlivaz contingent value rights (162.5) Successor equity value $ 1,194.8 (1) Represents non-operating assets and liabilities which were excluded from the enterprise value as put forth in the disclosure statement as there were no cash projections associated with these net assets. Upon the application of fresh-start accounting, the Company allocated the reorganization value to its individual assets based on their estimated fair values. Reorganization value represents the fair value of the Successor’s assets before considering liabilities. The following table reconciles the Company's enterprise value to its reorganization value as of the 2023 Effective Date: Enterprise value $ 2,950.0 Plus: Non-operating assets, net 290.0 Plus: Current liabilities (excluding debt or debt-like items) (1) 404.8 Plus: Other non-current liabilities (excluding debt or debt-like items) (2) 172.1 Reorganization value of Successor assets $ 3,816.9 (1) Excludes $7.6 million related to the current portion of the embedded derivative. (2) Excludes $15.0 million

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 29, 2023
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	4. Summary of Significant Accounting Policies Revenue Recognition Product Sales Revenue The Company sells its products through independent channels, including direct to retail pharmacies, end user customers and through distributors who resell the products to retail pharmacies, institutions and end user customers, while certain products are sold and distributed directly to hospitals. The Company also enters into arrangements with indirect customers, such as health care providers and payers, wholesalers, government agencies, institutions, managed care organizations and group purchasing organizations to establish contract pricing for certain products that provide for government-mandated and/or privately-negotiated rebates, sales incentives, chargebacks, distribution service agreements fees, fees for services and administration fees and discounts with respect to the purchase of the Company's products. Reserve for Variable Considerations Product sales are recorded at the net sales price (transaction price), which includes estimates of variable consideration for which reserves are established. These reserves result from estimated chargebacks, rebates, product returns and other sales deductions that are offered within contracts between the Company and its customers, health care providers and payers relating to the sale of the Company's products. These reserves are based on the amounts earned or to be claimed on the related sales and are classified as reductions of accounts receivable (if the amount is payable to the customer) or a current liability (if the amount is payable to a party other than a customer). Where appropriate, these estimates take into consideration a range of possible outcomes that are probability-weighted for relevant factors such as the Company's historical experience, estimated future trends, estimated customer inventory levels, current contracted sales terms with customers, level of utilization of the Company's products and other competitive factors. Overall, these reserves reflect the Company's best estimate of the amount of consideration to which it is entitled based on the terms of the contract. The amount of variable consideration that is included in the transaction price may be constrained (reduced) and is included in the net sales price only to the extent that it is probable that a significant reversal in the amount of the cumulative revenue recognized will not occur in a future period. The Company adjusts reserves for chargebacks, rebates, product returns and other sales deductions to reflect differences between estimated and actual experience. Such adjustments impact the amount of net sales recognized in the period of adjustment. Product sales are recognized when the customer obtains control of the Company's product. Control is transferred either at a point in time, generally upon delivery to the customer site, or in the case of certain of the Company's products, over the period in which the customer has access to the product and related services. Revenue recognized over time is based upon either consumption of the product or passage of time based upon the Company's determination of the measure that best aligns with how the obligation is satisfied. The Company's considerations of why such measures provide a faithful depiction of the transfer of its products are as follows: • For those contracts whereby revenue is recognized over time based upon consumption of the product, the Company either has: 1. the right to invoice the customer in an amount that directly corresponds with the value to the customer of the Company's performance to date, for which the practical expedient to recognize in proportion to the amount it has the right to invoice has been applied, or 2. the remaining goods and services to which the customer is entitled is diminished upon consumption. • For those contracts whereby revenue is recognized over time based upon the passage of time, the benefit that the customer receives from unlimited access to the Company's product does not vary, regardless of consumption. As a result, the Company's obligation diminishes with the passage of time; therefore, ratable recognition of the transaction price over the contract period is the measure that best aligns with how the obligation is satisfied. Transaction price allocated to the remaining performance obligations The majority of the Company's contracts have a term of less than one year; and the amount of transaction price allocated to the performance obligations that are unsatisfied at period end is generally expected to be satisfied within one year. Cost to obtain a contract As the majority of the Company's contracts are short-term in nature, sales commissions are generally expensed when incurred as the amortization period would have been less than one year. These costs are recorded within selling, general and administrative expense ("SG&A") in the consolidated statements of operations. For contracts that extend beyond one year, the incremental expense recognition matches the recognition of related revenue. Costs to fulfill a contract The Company capitalizes the costs associated with the devices used in the Company's portfolio of drug-device combination products, which are used in satisfaction of future performance obligations. Capital expenditures for these devices represent cash outflows for the Company's cost to produce the asset, which is classified in property, plant and equipment, net on the consolidated balance sheets and expensed to cost of sales over the useful life of the equipment. Product Royalty Revenues The Company licensed certain rights to Amitiza ® (lubiprostone) ("Amitiza") to third parties in exchange for royalties on net sales of the product. The Company recognized such royalty revenue as the related sales occurred. Contract Balances Accounts receivable are recorded when the right to consideration becomes unconditional. Payments received from customers are typically based upon payment terms of 30 days. The Company does not maintain contract asset balances aside from the accounts receivable balance as presented on the consolidated balance sheets as costs to obtain a contract are expensed when incurred as the amortization period would have been less than one year. These costs are recorded within SG&A on the consolidated statements of operations. Contract liabilities are recorded when cash payments are received in advance of the Company's performance, including amounts that are refundable. Taxes collected from customers relating to product sales and remitted to governmental authorities are accounted for on a net basis. Accordingly, such taxes are excluded from both net sales and expenses. Shipping and Handling Costs Shipping costs, which are costs incurred to physically move product from the Company's premises to the customer's premises, are classified as SG&A. Handling costs, which are costs incurred to store, move and prepare product for shipment, are classified as cost of sales. Shipping costs included in SG&A expenses in continuing operations were as follows: Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 Shipping costs $ 3.5 $ 22.3 $ 13.9 $ 12.8 $ 23.6 Research and Development Internal research and development costs are expensed as incurred. Research and development ("R&D") expenses include salary and benefits, allocated overhead and occupancy costs, clinical trial and related clinical manufacturing costs, contract services, medical affairs and other costs. From time to time, the Company has entered into licensing or collaborative agreements with third parties to develop a new drug candidate or intellectual property asset. These agreements may include R&D, marketing, promotion and selling activities to be performed by one or all parties involved. These collaborations generally include upfront, milestone and royalty or profit sharing payments contingent upon future events tied to the developmental and commercial success of the asset. In general, upfront and milestone payments made to third parties under these agreements are expensed as incurred up to the point of regulatory approval of the product. Milestone payments made to third parties upon regulatory approval are capitalized as an intangible asset and amortized to cost of sales over the estimated useful life of the related product. Currency Translation For the Company's non-U.S. subsidiaries that transact in a functional currency other than U.S. dollars, assets and liabilities are translated into U.S. dollars using fiscal year-end exchange rates. Revenues and expenses are translated at the average exchange rates in effect during the related month. The net effect of these translation adjustments is shown in the consolidated financial statements as a component of accumulated other comprehensive income (loss). From time to time, the Company has entered into derivative instruments to mitigate the exposure of movements in certain of these foreign currency transactions. Gains and losses resulting from foreign currency transactions are included in net loss. Cash and Cash Equivalents The Company classifies cash on hand and deposits in banks, including commercial paper, money market accounts and other investments it may hold from time to time, with an original maturity to the Company of three months or less, as cash and cash equivalents. Accounts Receivable and Allowance for Doubtful Accounts Trade accounts receivable are presented net of an allowance for doubtful accounts. The allowance for doubtful accounts reflects an estimate of losses inherent in the Company's accounts receivable portfolio determined on the basis of historical experience, current facts and circumstances, reasonable and supportable forecasts and other available evidence. Accounts receivable are written off when management determines they are uncollectible. Trade accounts receivable are also presented net of reserves related to chargebacks and rebates payable to customers with whom the Company has trade accounts receivable and the right of offset exists. Inventories Inventories are recorded at the lower of cost or net realizable value, primarily using the first-in, first-out convention. The Company reduces the carrying value of inventories for those items that are potentially excess, obsolete or slow-moving based on changes in customer demand, technology developments or other economic factors. Property, Plant and Equipment Property, plant and equipment is stated at cost less accumulated depreciation and impairment. Major renewals and improvements are capitalized, while routine maintenance and repairs are expensed as incurred. Depreciation for property, plant and equipment, other than land and construction in process, is generally based upon the following estimated useful lives, using the straight-line method: Buildings 10 to 45 years Leasehold improvements 1 to 20 years Capitalized software 1 to 10 years Machinery and equipment 1 to 20 years The Company capitalizes certain computer software and development costs incurred in connection with developing or obtaining software for internal use. Upon retirement or other disposal of property, plant and equipment, the cost and related amount of accumulated depreciation are eliminated from the asset and accumulated depreciation accounts, respectively. The difference, if any, between the net asset value and the proceeds is included in net loss. The Company assesses the recoverability of assets or asset groups using undiscounted cash flows whenever events or circumstances indicate that the carrying value of an asset or asset group may not be recoverable. If an asset or asset group is found to be impaired, the amount recognized for impairment is equal to the difference between the carrying value of the asset or asset group and its fair value. Leases The Company assesses all contracts at inception to determine whether a lease exists. The Company leases office space, manufacturing and warehousing facilities, equipment and vehicles, which are generally operating leases. Leases with an initial term of 12 months or less are not recorded on the consolidated balance sheet; the Company recognizes lease expense for these leases on a straight-line basis over the lease term. The Company has lease agreements with lease and non-lease components, which are accounted for separately. The Company's lease agreements generally do not contain variable lease payments or any material residual value guarantees. Lease assets and liabilities are recognized based on the present value of the future minimum lease payments over the lease term as of the commencement date. As the Company's leases do not generally provide an implicit rate, the Company utilizes its incremental borrowing rate based on the information available at commencement date in determining the present value of future lease payments. Most leases include one or more options to terminate or renew, with renewal terms that can extend the lease term from one to five years. The exercise of lease renewal options is at the Company's sole discretion. Termination and renewal options are included within the lease assets and liabilities only to the extent they are reasonably certain. Intangible Assets Intangible assets acquired in a business combination are recorded at fair value, while intangible assets acquired in other transactions are recorded at cost. Intangible assets with finite useful lives are amortized according to the pattern in which the economic benefit of the asset is used up over their estimated useful lives, as shown below. The estimated useful lives of the Company's intangible assets as of December 29, 2023 (Successor) were the following: Completed technology 1 to 20 years Amortization expense related to completed technology and certain other intangible assets is included in cost of sales. When a triggering event occurs, the Company evaluates potential impairment of finite-lived intangible assets by first comparing undiscounted cash flows associated with the asset, or the asset group they are part of, to its carrying value. If the carrying value is greater than the undiscounted cash flows, the amount of potential impairment is measured by comparing the fair value of the assets, or asset group, with their carrying value. The fair value of the intangible asset, or asset group, is estimated using an income approach. If the fair value is less than the carrying value of the intangible asset, or asset group, the amount recognized for impairment is equal to the difference between the carrying value of the asset and the fair value of the asset. The Company assesses the remaining useful life and the recoverability of finite-lived intangible assets whenever events or circumstances indicate that the carrying value of an asset may not be recoverable. The Company annually tests the indefinite-lived intangible assets for impairment, or whenever events or changes in circumstances indicate that the carrying value may not be recoverable by either a qualitative or income approach. The Company will compare the fair value of the assets with their carrying value and record an impairment when the carrying value exceeds the fair value. Contingencies The Company is subject to various legal proceedings and claims, including government investigations, environmental matters, product liability matters, patent infringement claims, antitrust matters, securities class action lawsuits, personal injury claims, employment disputes, contractual and other commercial disputes, and all other legal proceedings, all in the ordinary course of business as further discussed in Note 18. The Company records accruals for contingencies when it is probable that a liability has been incurred and the amount can be reasonably estimated. The Company discounts environmental liabilities using a risk-free rate of return when the obligation is fixed or reasonably determinable. The impact of the discount in the consolidated balance sheets was not material in any period presented. Legal fees, other than those pertaining to environmental matters, are expensed as incurred. Insurance recoveries related to potential claims are recognized up to the amount of the recorded liability when coverage is confirmed and the estimated recoveries are probable of payment. Assets and liabilities are not netted for financial statement presentation. Derivatives and hedging The Company evaluated the terms and features of its First-Out Takeback Term Loans, Second-Out Takeback Term Loans and Takeback Notes and identified an embedded feature that, in certain scenarios, could materially modify the cash flows of the respective debt instruments. The Company evaluated the embedded feature and determined that it was not clearly and closely related to the underlying debt instruments and did not qualify for any scope exceptions set forth in the accounting standards. Accordingly, this embedded feature is required to be bifurcated from its host instruments and accounted for separately as an embedded derivative liability. As a result, the Company recorded the fair value of the embedded derivatives as of the issuance date as a liability on its consolidated balance sheet. The embedded derivative will be adjusted to fair value each reported period with changes in fair value subsequent to the issuance date recognized within other income (expense) in the consolidated statements of operations. The fair value of the embedded derivative is reflected within current liabilities in the consolidated balance sheet as of December 29, 2023. The fair value of the derivative is determined using the with-and-without model which compares the estimated fair value of the underlying debt instruments with the embedded feature to the estimated fair value of the underlying debt instruments without the embedded feature, with the difference representing the estimated fair value of the embedded derivative feature. The with-and-without model includes significant unobservable estimates, including an estimation of the Company’s probability of an asset sale. Management estimates the probability of the asset sale based on its assessment of entity specific factors and the status of on-going transaction negotiations, if any. Changes in the inputs into the valuation model may have a significant impact on the estimated fair value of the embedded derivatives. For further details, refer to Note 19. Liabilities Subject to Compromise As a result of the commencement of the 2023 and 2020 Bankruptcy Proceedings, the payment of pre-petition liabilities was subject to compromise or other treatment pursuant to the 2023 and 2020 Plans. The determination of how liabilities would ultimately be settled or treated could not be made until the confirmed 2023 and 2020 Plans became effective. Accordingly, the ultimate amount of such liabilities was not determinable prior to the respective 2023 and 2020 Effective Dates. Pre-petition liabilities that were subject to compromise were reported at the amounts that were expected to be allowed by the Bankruptcy Court, even if they may be settled for different amounts. The amounts classified as LSTC prior to the 2023 and 2020 Effective Dates were preliminary and were subject to future adjustments dependent upon Bankruptcy Court actions, further developments with respect to disputed claims, determinations of the secured status of certain claims, the values of any collateral securing such claims, rejection of executory contracts, continued reconciliation or other events. Share-Based Compensation The Company recognizes the cost of employee services received in exchange for awards of equity or liability-based instruments based on the grant-date fair value of those awards. That cost is recognized over the period during which an employee is required to provide service in exchange for the award, the requisite service period (generally the vesting period). The cost for liability-based instruments is remeasured accordingly each reporting period throughout the requisite service period. Restructuring The Company recognizes charges associated with the Company's Board of Directors approved restructuring programs designed to transform its business and improve its cost structure. Restructuring charges can include severance costs, infrastructure charges, distributor contract cancellations and other items. The Company accrues for costs when they are probable and reasonably estimable. Income Taxes Deferred tax assets and liabilities are recognized for the expected future tax consequences of events that have been reflected in the consolidated financial statements. Deferred tax assets and liabilities are determined based on the differences between the financial reporting and tax bases of assets and liabilities and operating loss carryforwards, using tax rates expected to be in effect for the years in which the differences are expected to reverse. A valuation allowance is provided to reduce net deferred tax assets if, based upon the available evidence, it is more likely than not that some or all of the deferred tax assets will not be realized. The Company determines whether it is more likely than not that a tax position will be sustained upon examination. The tax benefit of any tax position that meets the more-likely-than-not recognition threshold is calculated as the largest amount that is more than 50.0% likely of being realized upon resolution of the uncertainty. To the extent a full benefit is not realized on the uncertain tax position, an income tax liability or a reduction to a deferred tax asset ("contra-DTA(s)") is established. Interest and penalties on income tax obligations, associated with uncertain tax positions, are included in the provision for income taxes. The calculation of the Company's tax liabilities involves dealing with uncertainties in the application of complex tax regulations in a multitude of jurisdictions across the Company's global operations. The Company adjusts these liabilities and contra-DTAs as a result of changing facts and circumstances; however, due to the complexity of some of these uncertainties, the ultimate resolution may result in a payment that is materially different from current estimates of the tax liabilities. If the Company's estimate of tax liabilities proves to be less than the ultimate assessment, an additional charge to expense would result. If payment of these amounts ultimately proves to be less than the recorded amounts, the reversal of the liabilities may result in income tax benefits being recognized in the period when it is determined that the liabilities are no longer necessary. Refer to Note 7 for further information regarding the classification of such amounts in the consolidated balance sheets. New Accounting Pronouncements Not Yet Adopted In November 2023, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") No. 2023-07, Segment Reporting: Improvements to Reportable Segment Disclosures . This guidance requires disclosure of incremental segment information on an annual and interim basis. This amendment is effective for fiscal year ending December 27, 2024 and interim periods within fiscal year ending December 26, 2025. The Company is currently assessing the impact of this guidance on its disclosures. In December 2023, the FASB issued ASU No. 2023-09, Income Taxes: Improvements to Income Tax Disclosures . This guidance requires consistent categories and greater disaggregation of information in the rate reconciliation and disclosures of income taxes paid by jurisdiction. This amendment is effective for fiscal year ending December 25, 2025 and interim periods within fiscal year ending December 26, 2026. The Company is currently assessing the impact of this guidance on its disclosures. No other new accounting pronouncement issued or effective during the fiscal year has had, or is expected to have, a material impact on the Company’s consolidated financial statements.

Revenue from Contracts with Cus

Revenue from Contracts with Customers (Notes)	12 Months Ended
	Dec. 29, 2023
Revenue from Contract with Customer [Abstract]
Revenue from Contract with Customer	5. Revenue from Contracts with Customers Product Sales Revenue See Note 20 for presentation of the Company's net sales by product family. Reserves for variable consideration The following table reflects activity in the Company's sales reserve accounts: Rebates and Chargebacks (1) Product Returns Other Sales Deductions Total Balance as of December 25, 2020 (Predecessor) 196.5 26.6 12.3 235.4 Provisions 2,087.1 23.7 55.2 2,166.0 Payments or credits (2,041.8) (28.8) (58.0) (2,128.6) Balance as of December 31, 2021 (Predecessor) 241.8 21.5 9.5 272.8 Provisions 693.4 5.2 17.1 715.7 Payments or credits (684.6) (8.1) (18.9) (711.6) Balance as of June 16, 2022 (Predecessor) $ 250.6 $ 18.6 $ 7.7 $ 276.9 Balance as of June 17, 2022 (Predecessor) $ 250.6 $ 18.6 $ 7.7 $ 276.9 Provisions 804.4 7.0 36.7 848.1 Payments or credits (789.7) (9.6) (31.7) (831.0) Balance as of December 30, 2022 (Predecessor) $ 265.3 $ 16.0 $ 12.7 $ 294.0 Provisions 1,368.8 9.9 43.3 1,422.0 Payments or credits (1,410.1) (13.1) (42.3) (1,465.5) Balance as of November 14, 2023 (Predecessor) $ 224.0 $ 12.8 $ 13.7 $ 250.5 Balance as of November 15, 2023 (Successor) $ 224.0 $ 12.8 $ 13.7 $ 250.5 Provisions 173.0 3.0 6.9 182.9 Payments or credits (195.4) (1.3) (9.3) (206.0) Balance as of December 29, 2023 (Successor) $ 201.6 $ 14.5 $ 11.3 $ 227.4 (1) Includes $59.0 million and $89.3 million of accrued Medicaid and $35.1 million and $55.3 million of accrued rebates as of December 29, 2023 (Successor) and December 30, 2022 (Predecessor), respectively, included within accrued and other current liabilities in the consolidated balance sheets. Product sales transferred to customers at a point in time and over time were as follows: Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 Product sales transferred at a point in time 85.3 % 83.2 % 83.0 % 80.8 % 79.4 % Product sales transferred over time 14.7 16.8 17.0 19.2 20.6 Transaction price allocated to the remaining performance obligations The following table includes estimated revenue from contracts extending greater than one year for certain of the Company's hospital products that are expected to be recognized in the future related to performance obligations that were unsatisfied or partially unsatisfied as of December 29, 2023 (Successor): Fiscal 2024 (1) $ 41.6 Fiscal 2025 (1) 23.7 Thereafter 4.2 (1) Certain estimated revenue included in the above table may not be recognized as a result of the Company's plan to cease commercialization of the StrataGraft product as further described in Note 22. Costs to fulfill a contract As of December 29, 2023 (Successor) and December 30, 2022 (Predecessor), the total net book value of the devices used in the Company's portfolio of drug-device combination products, which are used in satisfying future performance obligations and reflected in property, plant and equipment, net, on the consolidated balance sheets was $0.6 million and $10.3 million, respectively. The associated depreciation expense recognized during the period November 15, 2023 through December 29, 2023 (Successor), the period December 31, 2022 through November 14, 2023 (Predecessor), the period June 17, 2022 through December 30, 2022 (Predecessor), the period January 1, 2022 through June 16, 2022 (Predecessor), and fiscal 2021 (Predecessor) was zero, $1.9 million, $1.0 million, $2.9 million, and $6.1 million, respectively. Product Royalty Revenues The Company licensed certain rights to Amitiza to third parties in exchange for royalties on net sales of the product. Prior to 2023, the Company received a double-digit royalty based on a percentage of the gross profits of the licensed products sold during the term of the agreements. The Company recognized such royalty revenue as the related sales occurred. The associated royalty revenue recognized was as follows: Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 Royalty revenue $ 0.1 $ 4.3 $ 36.2 $ 34.9 $ 102.4

Restructuring and Related Charg

Restructuring and Related Charges	12 Months Ended
	Dec. 29, 2023
Restructuring and Related Activities [Abstract]
Restructuring and Related Charges	6. Restructuring and Related Charges During fiscal 2021 (Predecessor) and fiscal 2018 (Predecessor), the Company launched restructuring programs designed to improve its cost structure, neither of which has a specified time period. Charges of $50.0 million to $100.0 million were provided for under the 2021 program and $100.0 million to $125.0 million were provided for under the 2018 program. The 2021 program will commence upon substantial completion of the 2018 program, and has not commenced as of December 29, 2023 (Successor). In addition to the aforementioned restructuring programs, the Company has taken restructuring actions to generate synergies from its acquisitions. Net restructuring and related charges by segment were as follows: Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 Specialty Brands $ — $ — $ — $ — $ 0.1 Specialty Generics — — 0.8 3.5 4.9 Corporate — 1.7 11.3 6.1 24.0 Restructuring and related charges, net — 1.7 12.1 9.6 29.0 Less: accelerated depreciation — (0.8) (1.0) — (2.1) Restructuring charges, net $ — $ 0.9 $ 11.1 $ 9.6 $ 26.9 Net restructuring and related charges by program from continuing operations were comprised of the following: Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 2018 Program $ — $ 1.7 $ 12.1 $ 9.6 $ 29.0 Less: non-cash charges, including accelerated depreciation — (0.8) (2.2) (3.6) (6.3) Total charges expected to be settled in cash $ — $ 0.9 $ 9.9 $ 6.0 $ 22.7 The following table summarizes cash activity for restructuring reserves, substantially all of which related to contract termination costs, employee severance and benefits and exiting of certain facilities: 2018 Program Balance as of December 25, 2020 (Predecessor) $ 1.0 Charges from continuing operations 23.7 Changes in estimate from continuing operations (1.0) Cash payments (12.8) Balance as of December 31, 2021 (Predecessor) 10.9 Charges from continuing operations 7.1 Changes in estimate from continuing operations (1.1) Cash payments (15.9) Balance as of June 16, 2022 (Predecessor) $ 1.0 Balance as of June 17, 2022 (Predecessor) $ 1.0 Charges from continuing operations 12.7 Changes in estimate from continuing operations (2.8) Cash payments (6.3) Balance as of December 30, 2022 (Predecessor) 4.6 Charges from continuing operations 1.3 Changes in estimate from continuing operations (0.4) Cash payments (5.4) Balance as of November 14, 2023 (Predecessor) $ 0.1 Balance as of November 15, 2023 (Successor) and December 29, 2023 (Successor) $ 0.1 As of December 29, 2023 (Successor), net restructuring and related charges incurred cumulative to date for the 2018 Program were as follows: Specialty Brands $ 3.1 Specialty Generics 19.3 Corporate 96.9 $ 119.3 All of the restructuring reserves were included in accrued and other current liabilities on the Company's consolidated balance sheets. Amounts paid in the future may differ from the amount currently recorded.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 30, 2022
Income Tax Disclosure [Abstract]
Income Taxes	7. Income Taxes The domestic and international components (1) of loss from continuing operations before income taxes were as follows: Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 Domestic $ (46.1) $ (3,628.8) $ (359.4) $ (2,883.3) $ (512.2) International (0.1) 1,719.7 (290.9) 2,072.0 (317.6) Total $ (46.2) $ (1,909.1) $ (650.3) $ (811.3) $ (829.8) (1) Domestic reflects Ireland. Significant components (1) of income taxes related to continuing operations were as follows: Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 Current: Domestic $ (0.8) $ 36.6 $ (32.8) $ 33.7 $ (33.7) International (0.6) 4.7 5.7 (57.6) (12.7) Current income tax (benefit) provision (1.4) 41.3 (27.1) (23.9) (46.4) Deferred: Domestic (6.1) (300.6) (44.6) (82.3) (59.5) International (0.5) (18.5) 19.7 (391.1) (0.4) Deferred income tax (benefit) provision (6.6) (319.1) (24.9) (473.4) (59.9) Total $ (8.0) $ (277.8) $ (52.0) $ (497.3) $ (106.3) (1) Domestic reflects Ireland. The domestic current income tax provision reflects a tax benefit of zero, $2.9 million, $7.9 million, $4.1 million and $2.2 million from using NOL carryforwards for the period from November 15, 2023 through December 29, 2023 (Successor), the period from December 31, 2022 through November 14, 2023 (Predecessor), the period from June 17, 2022 through December 30, 2022 (Predecessor), the period from January 1, 2022 through June 16, 2022 (Predecessor) and fiscal 2021 (Predecessor), respectively. The international current income tax provision reflects a tax benefit of $6.9 million, $259.6 million, $61.0 million, $0.1 million and $1.2 million from using NOL carryforwards for the period from November 15, 2023 through December 29, 2023 (Successor), the period from December 31, 2022 through November 14, 2023 (Predecessor), the period from June 17, 2022 through December 30, 2022 (Predecessor), the period from January 1, 2022 through June 16, 2022 (Predecessor) and fiscal 2021 (Predecessor), respectively. During the period from November 15, 2023 through December 29, 2023 (Successor) and the period from December 31, 2022 through November 14, 2023 (Predecessor), net cash payments and net cash refunds for income taxes were $0.3 million and $128.0 million, respectively. Included within the net cash refunds of $128.0 million were refunds of $141.6 million received as a result of the provisions in the Coronavirus Aid, Relief and Economic Security ("CARES") Act. During the period from June 17, 2022 through December 30, 2022 (Predecessor) and the period from January 1, 2022 through June 16, 2022 (Predecessor), net cash payments for income taxes were $3.0 million and $3.0 million, respectively. During fiscal 2021 (Predecessor) net cash refunds for income taxes were $160.0 million, of which $178.8 million was received as a result of the provisions in the CARES Act. The reconciliation between domestic income taxes at the statutory rate and the Company's provision for income taxes on continuing operations is as follows: Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 Benefit for income taxes at domestic statutory income tax rate (1) $ (5.8) $ (238.6) $ (81.3) $ (101.4) $ (103.7) Adjustments to reconcile to income tax provision: Rate difference between domestic and international jurisdictions (2.2) 56.6 (4.7) 226.5 (224.9) Adjustments to accrued income tax liabilities and uncertain tax positions (2) — — — — (9.7) Credits, principally research and orphan drug — (1.9) — (0.9) (4.7) Permanently nondeductible and nontaxable items (3) (0.2) 3.2 3.1 (1.7) 9.8 Emergence — (103.7) — (31.6) — Withholding tax on Swiss distribution — — 4.7 — — Legal entity reorganization (4) — (44.7) — — — Reorganization items, net — 6.7 1.7 15.7 36.9 Other 0.1 0.6 (1.4) (3.1) 0.3 Valuation allowances (5) 0.1 44.0 25.9 (600.8) 189.7 (Benefit) provision for income taxes $ (8.0) $ (277.8) $ (52.0) $ (497.3) $ (106.3) (1) The statutory tax rate reflects the Irish statutory tax rate of 12.5%. (2) Includes interest and penalties on accrued income tax liabilities and uncertain tax positions. (3) For fiscal 2021 (Predecessor), the permanently nondeductible and nontaxable items were primarily driven by the Opioid-Related Litigation Settlement loss. (4) Associated unrecognized tax expense is netted within this line. (5) The period from January 1, 2022 through June 16, 2022 (Predecessor) consists of $512.1 million of tax benefit for the reduction in the valuation allowance on the Company's deferred tax assets due to the alleviation of the previous substantial doubt about the Company's ability to continue as a going concern. During the period from November 15, 2023 through December 29, 2023 (Successor), the rate difference between domestic and international jurisdictions was $2.2 million of tax benefit, which was primarily related to $3.7 million of tax benefit attributable to inventory step-up amortization expense and $0.2 million of tax benefit attributable to accretion expense associated with the Company's settlement obligation, offset by $0.3 million of tax expense attributable to amortization associated with the Company's debt and $1.4 million of tax expense predominately attributable to the pretax earnings in various jurisdictions. During the period from December 31, 2022 through November 14, 2023 (Predecessor), the rate difference between domestic and international jurisdictions was $56.6 million of a tax expense, which was primarily related to $48.9 million of tax expense attributable to reorganization items, net, and $35.0 million of tax expense predominately related to pretax earnings in various jurisdictions, offset by $15.7 million of tax benefit related to liabilities management and separation costs and $11.6 million of tax benefit related to non-restructuring impairment charges. During the period from June 17, 2022 through December 30, 2022 (Predecessor), the rate difference between domestic and international jurisdictions was $4.7 million of tax benefit, which was primarily related to $19.7 million of tax benefit attributable to inventory step-up amortization expense, $8.9 million of tax benefit attributable to accretion expense associated with our settlement liabilities and $6.3 million of tax benefit attributable to accretion expense associated with our debt offset by $30.2 million of tax expense predominately attributable to the pretax earnings in various jurisdictions. During the period from January 1, 2022 through June 16, 2022 (Predecessor), the rate difference between domestic and international jurisdictions was $226.5 million of tax expense, which was primarily related to $128.9 million of tax expense related to fresh-start adjustments, $103.4 million of tax expense attributable to gain on adjustments to LSTC and $12.8 million of tax expense predominately related to the pretax earnings in various jurisdictions offset by $18.6 million of tax benefit related to professional and lender fees. During fiscal year 2021 (Predecessor), the rate difference between domestic and international jurisdictions was $224.9 million of tax benefit, which was primarily related to $27.6 million of tax benefit attributable to reorganization items, net, $13.2 million of tax benefit attributable to non-restructuring impairment charges, $10.6 million of tax benefit attributable to the opioid-related litigation settlement loss, and $173.5 million of tax benefit predominately attributable to the pretax earnings in various jurisdictions. During the period from December 31, 2022 through November 14, 2023 (Predecessor), the Company recognized a tax benefit of $103.7 million upon emergence from the 2023 Bankruptcy Proceedings. These impacts of emergence consist of a $242.8 million tax benefit related to the revaluation of net deferred tax assets as a result of fresh-start accounting, offset by $139.1 million of tax expense related to permanently nondeductible impacts on fair value adjustments. During the period from January 1, 2022 through June 16, 2022 (Predecessor), the Company recognized a tax benefit of $31.6 million upon emergence from the 2020 Bankruptcy Proceedings. These impacts of emergence consist of a $1,202.0 million tax benefit related to the revaluation of net deferred tax assets as a result of fresh-start accounting and a $285.3 million tax benefit related to the release of uncertain tax positions, offset by $1,209.8 million of tax expense for the reduction in federal and state NOL carryforwards from the CODI realized upon emergence from bankruptcy and limitations under IRC Sections 382 and 383, $191.9 million of tax expense related to permanently nondeductible impacts on fair value adjustments, and $54.0 million of tax expense related to prepaid income taxes. As a result of the 2023 Plan and the 2020 Plan, the Company recognized CODI on its indebtedness, resulting in the utilization of, and reduction to, certain of its tax losses and tax credits in the U.S. and Luxembourg. The emergence from each of the respective 2023 and 2020 Bankruptcy Proceedings resulted in a change in ownership for purposes of IRC Section 382, causing the remaining U.S. tax losses, credits, and certain built in losses ("BILs") to be limited under IRC Sections 382 and 383. The amount of our pre-ownership change U.S. NOLs and BILs that can be utilized generally cannot exceed an amount equal to the product of (a) the applicable federal long-term tax-exempt rate in effect on the date of the ownership change and (b) the value of our U.S. affiliate stock immediately prior to the implementation of each respective plan ("382 Annual Limitation"). Evaluating the income tax impacts of each respective plan involves the interpretation of complex tax law and regulations which can be inherently uncertain and subject to varied interpretations. The 382 Annual Limitation for periods following the 2023 Effective Date is expected to be significant enough to be able to utilize all of the pre-ownership change U.S. attributes that are benefited in the consolidated financial statements; however, the utilization is expected to occur over a period of greater than 20 years and is dependent on the Company's generation of future taxable income. The portion of deferred tax assets associated with the tax losses and credits that are limited under IRC Section 382 or 383, and that have a remote possibility of being utilized, have been written off. The benefiting of the U.S. tax attributes required significant judgments made by management as to the expected amount and timing of the generation of future taxable income. With respect to non-U.S. deferred tax assets that have been recorded by the Company at emergence, the benefiting of the tax attributes is dependent on significant judgments made by management related to the generation of future taxable income. Based on current projections, the utilization is expected to occur over a period greater than 20 years. Refer to Note 4 for further information regarding the Company's income tax accounting policies. On December 20, 2021, the OECD released the Global Anti-Base Erosion ("GloBE") Model Rules ("Pillar Two") providing a legislative framework for the Income Inclusion Rule and the Under-Taxed Payment Rule ("UTPR"). Pillar Two is designed to ensure that large multinational enterprise groups pay a minimum level of tax on the income arising in each of the jurisdictions where they operate, principally creating a 15% minimum global effective tax rate. On December 15, 2022, the E.U. member states unanimously adopted a directive implementing the Pillar Two global minimum tax rules. On December 20, 2022, the OECD released three guidance documents related to Pillar Two. These documents included guidance on safe harbors and penalty relief and consultation papers on the GloBE Information Return and Tax Certainty for the GloBE rules. A number of jurisdictions have transposed the directive into national legislation with the rules to be applicable for fiscal years beginning on or after December 31, 2023, with the exception of the UTPR which is to be applicable for fiscal years beginning on or after December 31, 2024. The Company's fiscal year end of December 29, 2023 will allow the Company to postpone the effective date of these law changes by one year. The Company is closely monitoring developments and is evaluating the impacts these new rules will have on its tax rate, including the eligibility to qualify for the safe harbor rules. The following table summarizes the activity related to the Company's unrecognized tax benefits, excluding interest: Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 Balance at beginning of period $ 33.3 $ 24.8 $ 24.8 $ 333.5 $ 349.0 Additions related to current year tax positions — 8.5 — — — Additions related to prior period tax positions — — — — 9.3 Reductions related to prior period tax positions — — — (306.1) (2.8) Settlements — — — (2.6) (0.2) Lapse of statutes of limitations — — — — (21.8) Balance at end of period $ 33.3 $ 33.3 $ 24.8 $ 24.8 $ 333.5 Unrecognized tax benefits, excluding interest, were reported in the following consolidated balance sheet captions in the amounts shown: Successor Predecessor December 29, 2023 December 30, 2022 Deferred income tax asset 17.9 9.4 Other income tax liabilities 15.4 15.4 $ 33.3 $ 24.8 Total unrecognized tax benefits ("UTB(s)") of $30.1 million as of both December 29, 2023 (Successor) and November 14, 2023 (Predecessor), and $24.8 million as of both December 30, 2022 (Predecessor) and June 16, 2022 (Predecessor), if favorably settled, would benefit the effective tax rate. Total UTBs of $77.0 million as of December 31, 2021 (Predecessor), if favorably settled, would benefit the effective tax rate with the remaining reflected as a write-off of related other tax assets. During the period January 1, 2022 through June 16, 2022 (Predecessor), the decrease of $306.1 million primarily resulted from fresh-start adjustments. During fiscal 2021 (Predecessor), due to a lapse of statutes of limitations, $5.1 million of tax and interest on unrecognized tax benefits related to the Nuclear Imaging business were eliminated, and a benefit of $5.1 million was recorded in discontinued operations within the consolidated statement of operations. The Company recorded zero accrued interest and penalties for the period November 15, 2023 through December 29, 2023 (Successor) and an increase to accrued interest and penalties of $1.4 million during the period December 31, 2022 through November 14, 2023 (Predecessor). Interest and penalties activity during the period from June 17, 2022 through December 30, 2022 (Predecessor), the period from January 1, 2022 through June 16, 2022 (Predecessor) and fiscal 2021 (Predecessor), was a net increase of $0.6 million, a net decrease of $16.7 million, and a net increase of $2.2 million, respectively. The total amount of accrued interest and penalties related to uncertain tax positions was $4.2 million and $2.8 million as of December 29, 2023 (Successor) and December 30, 2022 (Predecessor), respectively. Within the next twelve months, the unrecognized tax benefits and the related interest and penalties are not expected to significantly increase or decrease. Certain of the Company's subsidiaries continue to be subject to examination by taxing authorities. The earliest open year subject to examination for the U.S. federal and the U.S. state is 2015 and 2013, respectively. The earliest open year subject to examination in other jurisdictions, including Ireland, Japan, Luxembourg, Switzerland and the U.K. is 2014. Income taxes payable, including uncertain tax positions and related interest accruals, was reported in the following consolidated balance sheet captions in the amounts shown: Successor Predecessor December 29, 2023 December 30, 2022 Accrued and other current liabilities $ 1.7 $ 3.6 Other income tax liabilities 19.6 18.2 $ 21.3 $ 21.8 Tax receivables were included in the following consolidated balance sheet captions in the amounts shown: Successor Predecessor December 29, 2023 December 30, 2022 Prepaid expenses and other current assets 11.5 179.5 Deferred income taxes result from temporary differences between the amount of assets and liabilities recognized for financial reporting and tax purposes. The components of the net deferred tax asset (liability) at the end of each fiscal year were as follows: Successor Predecessor December 29, 2023 December 30, 2022 Deferred tax assets: Tax loss and credit carryforward $ 3,600.7 $ 3,646.0 Capital tax loss carryforward and related assets 983.5 1,412.6 Intangible assets 571.5 278.4 Opioid-Related Litigation Settlement liability — 111.7 Excess interest 95.1 84.0 Other 231.3 159.8 5,482.1 5,692.5 Deferred tax liabilities: Investment in partnership (68.7) (67.4) Other (28.6) (157.0) (97.3) (224.4) Net deferred tax asset before valuation allowances 5,384.8 5,468.1 Valuation allowances (4,583.8) (4,992.9) Net deferred tax asset (liability) $ 801.0 $ 475.2 The net deferred tax asset before valuation allowances was $5,384.8 million as of December 29, 2023 (Successor), compared to $5,468.1 million as of December 30, 2022 (Predecessor). This decrease consists of $434.3 million of a decrease related to the expiration of capital tax loss related assets and $111.7 million of a decrease related to the Opioid-Related Litigation Settlement offset by $252.5 million of an increase related to fresh-start activity, $110.5 million of an increase predominately related to tax loss and other operational activity, and $99.7 million of an increase associated with amortization of intangible assets. The $252.5 million increase related to fresh-start activity consists of fair value adjustments related to intangible assets and other deferred tax liabilities. The deferred tax asset valuation allowances were $4,583.8 million and $4,992.9 million as of December 29, 2023 (Successor) and December 30, 2022 (Predecessor), respectively. The valuation allowances as of both December 29, 2023 (Successor) and December 30, 2022 (Predecessor) relate primarily to the uncertainty of the utilization of certain deferred tax assets, driven by domestic and international net operating and capital losses, credits, and intangible assets. Deferred taxes were included in the following consolidated balance sheet captions in the amounts shown: Successor Predecessor December 29, 2023 December 30, 2022 Deferred income tax asset $ 801.0 $ 475.5 Deferred income tax liability — (0.3) Net deferred tax asset (liability) $ 801.0 $ 475.2 As of December 29, 2023 (Successor), the Company had approximately $3,552.1 million of NOL carryforwards in certain international jurisdictions measured at the applicable statutory rates, of which $1,371.9 million have no expiration and the remaining $2,180.2 million will expire in future years through 2039. As of December 29, 2023 (Successor), the Company had $46.9 million of domestic NOL carryforwards measured at the applicable statutory rates, which have no expiration date. As of December 29, 2023 (Successor), the Company had $13.9 million of capital loss carryforwards in certain international jurisdictions measured at the applicable statutory rates, which will expire in 2028. As of December 29, 2023 (Successor), the Company had approximately $969.6 million of domestic capital loss carryforwards measured at the applicable statutory rates, which have no expiration date. As of December 29, 2023 (Successor), the Company had $1.7 million of tax credits available to reduce future income taxes payable, in international jurisdictions, which will expire in future years through 2043. As of December 29, 2023 (Successor), the Company's taxable financial reporting basis in subsidiaries exceeded its corresponding tax basis by $3.4 million. Such excess amount is indefinitely reinvested and it is not practicable to determine the associated potential tax liability due to the complexity of the Company's legal entity structure as well as the timing, extent, and nature of any hypothetical realization.

Earnings (Loss) per Share

Earnings (Loss) per Share	12 Months Ended
	Dec. 29, 2023
Earnings (Loss) per Share [Abstract]
Earnings (Loss) per Share	8. Loss per Share Loss per share is computed by dividing net loss by the number of weighted-average shares outstanding during the period. Dilutive securities, including participating securities, have not been included in the computation of loss per share as the Company reported a net loss from continuing operations during all periods presented below and therefore, the impact would have been anti-dilutive. The weighted-average number of shares outstanding used in the computations of both basic and diluted loss per share were as follows ( in millions ): Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 Basic 19.7 13.3 13.2 84.8 84.7 The computation of diluted weighted-average shares outstanding for the period November 15, 2023 through December 29, 2023 (Successor), the period December 31, 2022 through November 14, 2023 (Predecessor), the period June 17, 2022 through December 30, 2022 (Predecessor), the period January 1, 2022 through June 16, 2022 (Predecessor), and fiscal 2021 (Predecessor) excluded approximately 1.0 million, zero, zero, 0.5 million, and 5.2 million shares of equity awards, respectively, because the effect would have been anti-dilutive.

Inventories

Inventories	12 Months Ended
	Dec. 29, 2023
Inventory, Net [Abstract]
Inventories	9. Inventories Inventories were comprised of the following at the end of each period: Successor Predecessor December 29, December 30, Raw materials $ 98.0 $ 80.2 Work in process 501.8 552.1 Finished goods 382.9 315.3 Inventories $ 982.7 $ 947.6

Property, Plant and Equipment

Property, Plant and Equipment	12 Months Ended
	Dec. 29, 2023
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	10. Property, Plant and Equipment The gross carrying amount and accumulated depreciation of property, plant and equipment were comprised of the following at the end of each period: Successor Predecessor December 29, 2023 December 30, 2022 Land $ 37.7 $ 51.0 Buildings 94.6 127.2 Capitalized software 1.9 17.5 Machinery and equipment 136.3 216.8 Construction in process 60.8 72.5 331.3 485.0 Less: accumulated depreciation (9.6) (27.4) Property, plant and equipment, net $ 321.7 $ 457.6 Depreciation expense was as follows: Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 Depreciation expense $ 9.6 $ 40.7 $ 28.8 $ 40.0 $ 94.7

Leases (Notes)

Leases (Notes)	12 Months Ended
	Dec. 29, 2023
Leases [Abstract]
Lessee, Operating Leases	11. Leases Lease assets and liabilities related to the Company's operating leases are reported in the following consolidated balance sheet captions: Successor Predecessor December 29, December 30, Other assets $ 50.9 $ 38.1 Accrued and other current liabilities $ 10.5 $ 10.3 Other liabilities 44.8 30.4 Total lease liabilities $ 55.3 $ 40.7 Dependent on the nature of the leased asset, lease expense is included within cost of sales or SG&A. The primary components of lease expense were as follows: Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 Lease cost: Operating lease cost $ 1.8 $ 15.0 $ 7.9 $ 8.7 $ 19.6 Short-term lease cost 0.5 0.9 1.6 0.4 1.1 Variable lease cost — 2.3 1.5 1.2 2.4 Total lease cost $ 2.3 $ 18.2 $ 11.0 $ 10.3 $ 23.1 Lease terms and discount rates were as follows: Successor Predecessor December 29, December 30, Weighted-average remaining lease term (in years) - operating lease 7.4 6.7 Weighted-average discount rate - operating leases 8.1 % 11.9 % Contractual maturities of operating lease liabilities as of December 29, 2023 (Successor) were as follows: Fiscal 2024 $ 14.4 Fiscal 2025 13.2 Fiscal 2026 8.9 Fiscal 2027 6.9 Fiscal 2028 6.6 Thereafter 24.7 Total lease payments 74.7 Less: Interest (19.4) Present value of lease liabilities $ 55.3 Other supplemental cash flow information related to leases were as follows: Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 2.4 $ 14.6 $ 9.2 $ 9.4 $ 20.4 Lease assets obtained in exchange for lease obligations: Operating leases — 13.2 7.1 13.4 2.6

Goodwill and Intangible Assets

Goodwill and Intangible Assets	12 Months Ended
	Dec. 29, 2023
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	12. Intangible Assets Intangible Assets The gross carrying amount and accumulated amortization of intangible assets were comprised of the following at the end of each period: Successor Predecessor December 29, 2023 December 30, 2022 Gross Carrying Amount Accumulated Amortization Gross Carrying Amount Accumulated Amortization Amortizable: Completed technology $ 624.6 $ 16.2 $ 3,041.2 $ 318.7 Non-Amortizable: In-process research and development — 121.3 The Company recorded impairment charges related to its Specialty Brands segment totaling $50.1 million and $154.9 million during the period from December 31, 2022 through November 14, 2023 (Predecessor) and fiscal 2021 (Predecessor), respectively. The valuation method used to approximate fair value in each of these periods was based on the estimated discounted cash flows for the respective asset. The impairment charge during the period from December 31, 2022 through November 14, 2023 (Predecessor) was related to StrataGraft due to lower than anticipated cash flows and the fiscal 2021 (Predecessor) impairment charge included a partial impairment of $90.4 million related to Amitiza as the undiscounted cash flows were less than its net book value, and a full impairment of $64.5 million related to MNK-6105 and MNK-6106 as the Company decided it would no longer pursue further development of this in-process research and development ("IPR&D") asset. The Company recorded impairment charges related to its Specialty Generics segment totaling $85.8 million during the period from December 31, 2022 through November 14, 2023 (Predecessor). The valuation method used to approximate fair value was based on the estimated discounted cash flows. The Company has decided it will no longer pursue further development of the IPR&D assets and as a result, recognized a full impairment. As part of fresh-start accounting, as of the 2023 Effective Date, the Company wrote-off the existing intangible assets and accumulated amortization of the Predecessor and recorded $624.6 million to reflect the fair value of intangible assets of the Successor (see also Note 3). Intangible assets of the Successor as of the 2023 Effective Date consisted of the following: Carrying Amount Amortization Method Amortization Period (in years) Discount Rate Segment Amortizable completed technology: Acthar Gel $ 110.0 Sum of the years digits 10.0 52.3% Specialty Brands Therakos 129.4 Sum of the years digits 9.0 51.5 Specialty Brands Amitiza 12.3 Sum of the years digits 1.0 51.5 Specialty Brands INOmax 41.3 Sum of the years digits 8.0 51.5 Specialty Brands Terlivaz 68.1 Straight-line 5.5 52.5 Specialty Brands Generics 186.7 Straight-line 18.0 14.1 Specialty Generics APAP 76.8 Straight-line 20.0 13.5 Specialty Generics $ 624.6 Amitiza Beginning January 1, 2022 (Predecessor), the Company changed its amortization method used for the Amitiza intangible asset from the straight-line method to the sum of the years digits method, an accelerated method of amortization, to more accurately reflect the consumption of economic benefits over the remaining useful life of the asset. This change in amortization method resulted in additional amortization expense of $21.7 million, which impacted basic loss per share by $0.26 for the period January 1, 2022 through June 16, 2022 (Predecessor). Intangible asset amortization expense Intangible asset amortization expense was as follows: Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 Amortization expense $ 16.2 $ 449.6 $ 318.7 $ 281.8 $ 581.1 The estimated aggregate amortization expense on intangible assets owned by the Company and being amortized as of December 29, 2023 (Successor) is expected to be as follows: Fiscal 2024 $ 90.3 Fiscal 2025 74.8 Fiscal 2026 68.4 Fiscal 2027 62.0 Fiscal 2028 55.6

Debt

Debt	12 Months Ended
	Dec. 29, 2023
Debt Disclosure [Abstract]
Debt Disclosure	13. Debt Debt was comprised of the following at the end of each period: Successor Predecessor December 29, 2023 December 30, 2022 Principal Carrying Value (1) Unamortized Discount and Debt Issuance Costs Principal Carrying Value (2) Unamortized Discount and Debt Issuance Costs First-Out Takeback Term Loan due November 2028 $ 228.8 $ 243.4 $ — $ — $ — $ — Second-Out Takeback Term Loan due November 2028 640.4 685.5 — — — — 14.75% Second-Out Takeback Notes due November 2028 778.6 836.4 — — — — Receivables financing facility due December 2027 — — 2.9 — — — 10.00% first lien senior secured notes due April 2025 — — — 495.0 475.9 — 10.00% second lien senior secured notes due April 2025 — — — 321.9 242.2 — 2017 Replacement Term loan due September 2027 — — — 1,374.1 1,222.1 — 2018 Replacement Term loan due September 2027 — — — 364.8 326.9 — 11.50% first lien senior secured notes due December 2028 — — — 650.0 650.0 20.8 10.00% second lien senior secured notes due June 2029 — — — 328.3 175.5 — Total debt 1,647.8 1,765.3 2.9 3,534.1 3,092.6 20.8 Less: Current portion (6.5) (6.5) — (44.1) (44.1) — Total long-term debt, net of current portion $ 1,641.3 $ 1,758.8 $ 2.9 $ 3,490.0 $ 3,048.5 $ 20.8 (1) Upon adoption of fresh-start accounting upon the emergence from the 2023 Bankruptcy Proceedings, the Company recorded its debt instruments at fair value utilizing the Black-Derman-Toy model, which takes into consideration prepayment options and a credit-adjusted discount rate. Subsequent to the 2023 Effective Date, the Company accounted for its debt instruments utilizing the amortized cost method and amortizes the fair value premium to the principal amount over the term of the respective instruments. Such amortization expense is reflected as interest expense on the consolidated statement of operations for the Successor period. (2) Upon adoption of fresh-start accounting upon the emergence from the 2020 Bankruptcy Proceedings, the Company recorded its debt instruments at fair value utilizing the Black-Derman-Toy model, which takes into consideration prepayment options and a credit-adjusted discount rate. Subsequent to the 2020 Effective Date up through the 2023 Petition Date, the Company accounted for its debt instruments utilizing the amortized cost method and accreted the fair value discount to the principal amount over the term of the respective instruments. Such accretion expense was reflected as interest expense on the consolidated statement of operations for the Predecessor period. As of the petition date of the 2023 Bankruptcy Proceedings, the Company expensed $377.6 million of accelerated accretion to adjust the carrying value up to the principal value or allowed claim amount pursuant to the 2023 Plan and recorded the expense within reorganization items, net in the consolidated statement of operations for the period from December 31, 2022 to November 14, 2023 (Predecessor). Additionally, as a result of the 2023 Bankruptcy Proceedings, the Company expensed $18.5 million of unamortized discount and debt issuance costs, net, recorded in reorganization items, net in the consolidated statement of operations for the period from December 31, 2022 to November 14, 2023 (Predecessor). Refer to Note 3 for further information on reorganization items, net. The commencement of the 2023 Chapter 11 Cases constituted an event of default under certain of the Predecessor's debt agreements. As a result of the 2023 Chapter 11 Cases, the principal and interest due under these debt instruments became immediately due and payable. However, any efforts to enforce payment was automatically stayed in accordance with the applicable provisions of the Bankruptcy Code. On the 2023 Effective Date, $1,716.8 million of First Lien Term Loans, $495.0 million in aggregate principal amount of 2025 First Lien Notes, $650.0 million in aggregate principal amount of 2028 First Lien Notes, $321.9 million in aggregate principal amount of 2025 Second Lien Senior Notes and $328.3 million in aggregate principal amount of 2029 Second Lien Senior Notes were canceled and the Company entered into the new Takeback Term Loans and the Takeback Notes. Successor Indebtedness New Takeback Debt On the 2023 Effective Date and pursuant to the 2023 Plan, the Issuers (i) entered into a new senior secured first lien term loan facility with an aggregate principal amount of approximately $871.4 million, consisting of approximately $229.4 million of First-Out Takeback Term Loans and approximately $642.0 million of Second-Out Takeback Term Loans, pursuant to the credit agreement and (ii) issued approximately $778.6 million in aggregate principal amount of Takeback Notes pursuant to the indenture. All DIP Claims under the DIP Credit Agreement not otherwise satisfied in cash were converted on a dollar-for-dollar basis into First-Out Takeback Term Loans. Each holder of an allowed claim related to the outstanding 2025 First Lien Notes, the outstanding 2028 First Lien Notes, or the First Lien Term Loans elected to receive such Takeback Debt either in the form of Second-Out Takeback Term Loans or Takeback Notes. All obligations of the Issuers under the Takeback Debt are unconditionally guaranteed, on a joint and several basis, by each of the obligors of the previously issued First Lien Term Loans, 2025 First Lien Notes and 2028 First Lien Notes (collectively, the "First Lien Debt"), subject to certain limited exceptions (including the exclusion of Mallinckrodt Petten Holdings B.V.) (collectively, the "Guarantors"). The Takeback Debt is secured by a first priority lien and security interest in substantially all collateral that secured the First Lien Debt and substantially all previously unencumbered property of the Issuers and the Guarantors, other than (i) any receivables or related assets transferred to, or constituting collateral for, the Amended ABL Credit Agreement, dated as of June 16, 2022, as amended on August 23, 2023, by and among ST US AR Finance LLC, the lenders party thereto, the L/C Issuers (as defined therein) party thereto and Barclays Bank plc, as administrative agent and collateral agent ("Post-Petition A/R Facility"), (ii) the equity of ST US AR Finance LLC, the non-Debtor subsidiary of the Company that is the borrower under the Post-Petition A/R Facility, and (iii) certain other customary exceptions. The Takeback Debt is governed by the terms of a first lien intercreditor agreement, dated as of the 2023 Effective Date ("Intercreditor Agreement"), by and among the Issuers, the Company, the other grantors from time to time party thereto, Acquiom Agency Services LLC, as Collateral Agent and as credit agreement authorized representative, Wilmington Savings Fund Society, FSB, as initial additional authorized representative, and each additional authorized representative from time to time party thereto. The First-Out Takeback Term Loans rank senior in waterfall priority to the Second-Out Takeback Term Loans and the Takeback Notes. The Second-Out Takeback Term Loans rank pari passu in waterfall priority to the Takeback Notes. The First-Out Takeback Term Loans mature on November 14, 2028 and bear interest at a rate equal to SOFR plus 7.50% per annum, subject to a SOFR floor of 4.50%, or in the case of an ABR Loan (as defined in the Credit Agreement), ABR (as defined in the Credit Agreement) plus 6.50% per annum, and amortize quarterly on the last day of each March, June, September and December of each year, at a rate of 1.00% per annum, commencing December 29, 2023. The Second-Out Takeback Term Loans mature on November 14, 2028 and bear interest at a rate equal to SOFR plus 9.50% per annum, subject to a SOFR floor of 4.50%, or in the case of an ABR Loan, ABR plus 8.50% per annum, and amortize quarterly on the last day of each March, June, September and December of each year, at a rate of 1.00% per annum, commencing December 29, 2023. The Takeback Notes mature on November 14, 2028 and bear interest at a rate equal to 14.75% payable semi-annually in arrears on each May 15 and November 15, commencing May 15, 2024. The Credit Agreement contains certain customary affirmative and negative covenants, representations and warranties and events of default (including as a result of a change of control), subject in certain cases to customary grace and cure periods. The occurrence of an event of default under the Credit Agreement could result in the acceleration of all outstanding borrowings under the Takeback Term Loans and could cause a cross-default that could result in the acceleration of other indebtedness of the Company and its subsidiaries. The indenture contains certain customary affirmative and negative covenants and events of default (including as a result of a change of control), subject in certain cases to customary grace and cure periods. The occurrence of an event of default under the indenture could result in the acceleration of the Takeback Notes and could cause a cross-default that could result in the acceleration of other indebtedness of the Company and its subsidiaries. The Takeback Debt is subject to (i) mandatory prepayment or redemption, as applicable, with the net proceeds of certain asset sales and recovery events, subject to customary exceptions, at a prepayment price equal to 100% of the principal amount thereof plus a make-whole premium (for the first two years following issuance of the Takeback Debt) and accrued and unpaid interest, and (ii) mandatory prepayment or repurchase (at the option of each lender thereunder) with 50% of excess cash flow (for the excess cash flow period ending December 27, 2024, to the extent excess cash flow exceeds $100 million) at a prepayment price equal to 100% of the principal amount thereof plus accrued and unpaid interest. The Company determined that the Takeback Debt includes an embedded feature that requires mandatory prepayment with the net proceeds of certain asset sales and recovery events, subject to customary exceptions, at a prepayment price equal to 100% of the principal amount thereof plus a make-whole premium ("Applicable Premium") for the first two years following issuance of the Takeback Debt and accrued and unpaid interest. The Applicable Premium shall mean an amount equal to the greater of (i) 1% of the principal amount of the Takeback Debt prepaid and (ii) the excess, if any, of (A) the sum of (1) all required interest payable on the principal amount of such Initial Term Loans subject to the applicable prepayment from the date of such prepayment through (and including) the second anniversary of the valuation date (as if such Initial Term Loans has been outstanding) calculated over an interest period of three months in effect on the third business day prior to such prepayment plus (2) the principal amount of such Initial Term Loans subject to the applicable prepayment, in each case, discounted to the date of such prepayment on a semi-annual basis (assuming a 360-day year consisting of twelve 30-day months) at the treasury rate as of such date of determination plus 50 basis points, over (B) the principal amount of such Initial Term Loans subject to the applicable prepayment. This mandatory prepayment feature was determined to not be clearly and closely related to the debt host contract and required to be bifurcated and recognized at fair value on the consolidated balance sheet. The Company estimated the fair value of the embedded derivative to be $15.1 million. Refer to Note 19 for further information. Accounts Receivable Financing Facility On the 2020 Effective Date, MEH, Inc. ("MEH"), as servicer, ST US AR Finance LLC, a direct wholly owned subsidiary of MEH ("ST US AR"), as borrower, the lenders party thereto, and the letter of credit issuers party thereto entered into a receivables financing facility ("Receivables Financing Facility") pursuant to an ABL Credit Agreement ("Receivables Financing Credit Agreement") and a Purchase and Sale Agreement ("Purchase and Sale Agreement"). Under the Receivables Financing Facility, ST US AR may borrow money up to an amount based on a borrowing base with a maximum draw of up to $200.0 million, which may vary depending on the underlying receivables amount. Borrowings are secured by a first-lien security interest under the Receivables Financing Facility on existing and future accounts receivables and related assets that have been sold from certain subsidiaries of MEH to ST US AR. The Receivables Financing Facility includes customary affirmative and negative covenants for transactions of this type. From the closing date until the last day of the first fiscal quarter after the closing date, borrowings bore interest at a rate of (a) either (i) the alternate base rate or (ii) SOFR, and (b) an applicable margin. On the first day of each fiscal quarter thereafter, the applicable margins are determined from a pricing grid based upon the historical excess availability for the most recent fiscal quarter ended immediately prior. On August 23, 2023, the Company entered into an amendment with the lenders and agents under the Receivables Financing Facility Credit Agreement ("ABL Amendment"), by and among ST US AR, the lenders party thereto, the L/C Issuers (as defined in the Receivables Financing Facility Credit Agreement) party thereto and Barclays Bank plc, as administrative agent ("Administrative Agent") and collateral agent (as amended, the "Amended ABL Credit Agreement"). The Receivables Financing Facility matures on the earlier of December 16, 2027 and a date that is 91 days prior to the maturity date of any other material indebtedness that is incurred after the closing date. ST US AR may borrow, pay or prepay and reborrow under the Receivables Financing Facility at any time. So long as there is not an overadvance under the Receivables Financing Facility, and subject to certain other conditions, ST US AR can elect to repay borrowings or use cash to make distributions to MEH and certain subsidiaries of MEH that have contributed receivables to ST US AR. The obligations under the Receivables Financing Facility are not guaranteed by MEH or any of its restricted subsidiaries. The Receivables Financing Facility is subject to customary events of defaults for transactions of this type. As of December 29, 2023 (Successor), the Company had no outstanding borrowings on its Receivables Financing Facility. Predecessor Indebtedness Pursuant to the 2023 Plan and the 2023 Scheme of Arrangement, on the 2023 Effective Date, each holder of an allowed claim related to the outstanding First Lien Debt received its pro rata share of (A) 92.3% of the Successor ordinary shares (subject to dilution from equity reserved under the MIP and the Opioid CVRs, if equity settled), (B) cash in an amount sufficient to repay in full (i) the accrued and unpaid interest on the First Lien Term Loans in the case of any holder of the First Lien Term Loans, (ii) the accrued and unpaid interest on the 2025 First Lien Notes in the case of any holder of 2025 First Lien Notes, and (iii) the accrued and unpaid interest on the 2028 First Lien Notes in the case of any holder of the 2028 First Lien Notes; and (C) the Second-Out Takeback Debt in satisfaction thereof. Furthermore, on the 2023 Effective Date, the 2023 Debtors paid in cash certain outstanding fees, expenses and costs of the agents and trustees related to the First Lien Debt. As a result of the satisfaction of the First Lien Debt pursuant to the 2023 Plan and the 2023 Scheme of Arrangement, the Company and its subsidiaries terminated the First Lien Debt and the indentures and agreements related thereto. Pursuant to the 2023 Plan and the 2023 Scheme of Arrangement, on the 2023 Effective Date, each holder of an allowed claim related to then outstanding Second Lien Notes received its pro rata share of 7.7% of the Successor ordinary shares (subject to dilution from equity reserved under the MIP and the Opioid CVRs, if equity settled) in satisfaction thereof. Furthermore, on the 2023 Effective Date, the 2023 Debtors paid in cash certain outstanding fees, expenses and costs of the agents and trustees related to the Second Lien Notes. As a result of the satisfaction of the Second Lien Notes pursuant to the 2023 Plan and the 2023 Scheme of Arrangement, the Company and its subsidiaries terminated the Second Lien Notes and the indentures related thereto. Applicable interest rate As of December 29, 2023 (Successor), the applicable interest rate and outstanding principal on the Company's debt instruments were as follows: Applicable interest rate Outstanding principal Fixed-rate instrument 14.8 % $ 778.6 First-Out Takeback Term Loans (1) 11.4 228.8 Second-Out Takeback Term Loans (1) 13.4 640.4 (1) Includes the impact of the interest rate cap agreement, which is discussed further in Note 19. The Company's stated long-term debt principal maturity amounts as of December 29, 2023 are as follows: Fiscal 2024 $ 6.5 Fiscal 2025 8.7 Fiscal 2026 8.7 Fiscal 2027 10.9 Fiscal 2028 1,613.0

Retirement Plans

Retirement Plans	12 Months Ended
	Dec. 29, 2023
Retirement Benefits [Abstract]
Retirement Plans	14. Retirement Plans Defined Benefit Plans The Company sponsors a number of defined benefit retirement plans covering certain of its U.S. employees and non-U.S. employees. As of December 29, 2023 (Successor), U.S. plans represented 31.4% of the Company's remaining projected benefit obligation. The Company generally does not provide postretirement benefits other than retirement plan benefits for its employees; however, certain of the Company's U.S. employees participate in postretirement benefit plans that provide medical benefits. These plans are unfunded. The benefit obligation recognized on the consolidated balance sheets were $18.9 million and $18.7 million as of December 29, 2023 (Successor) and December 30, 2022 (Predecessor), respectively, for pension benefits and $25.9 million and $26.8 million as of December 29, 2023 (Successor) and December 30, 2022 (Predecessor), respectively, for postretirement benefits. The weighted-average discount rate to determine benefit obligations for the Company's pension and postretirement benefit plans ranged from 5.4% to 5.6%. For the Company's unfunded U.S. plans, the discount rate is based on the market rate for a broad population of AA-rated (Moody's Investor Services, Inc. or Standard & Poor's Corporation) corporate bonds over $250.0 million. Defined Contribution Retirement Plans The Company maintains one active tax-qualified 401(k) retirement plan and one active non-qualified deferred compensation plan in the U.S. The 401(k) retirement plan provides for an automatic Company contribution of 3% of an eligible employee's pay, with an additional Company matching contribution generally equal to 50.0% of each employee's elective contribution to the plan up to 8% of the employee's eligible pay. The deferred compensation plan permitted eligible employees to defer a portion of their compensation. The deferred compensation plan is currently frozen for employee deferrals. Total defined contribution expense was $2.5 million, $18.6 million, $7.8 million, $9.6 million, and $22.2 million for the period November 15, 2023 through December 29, 2023 (Successor), the period December 31, 2022 through November 14, 2023 (Predecessor), the period June 17, 2022 through December 30, 2022 (Predecessor), the period January 1, 2022 through June 16, 2022 (Predecessor), and fiscal 2021 (Predecessor), respectively. Rabbi Trusts and Other Investments The Company maintains several rabbi trusts, the assets of which are used to pay retirement benefits. The rabbi trust assets are subject to the claims of the Company's creditors in the event of the Company's insolvency. Plan participants are general creditors of the Company with respect to these benefits. The trusts primarily hold life insurance policies and debt and equity securities, the value of which is included in other assets on the consolidated balance sheets. Note 19 provides additional information regarding the debt and equity securities. The carrying value of the 48 and 55 life insurance contracts held by these trusts was $38.0 million and $39.5 million as of December 29, 2023 (Successor) and December 30, 2022 (Predecessor), respectively. These contracts had a total death benefit of $74.2 million and $81.0 million as of December 29, 2023 (Successor) and December 30, 2022 (Predecessor), respectively. However, there are outstanding loans against the policies amounting to $18.3 million and $21.6 million as of December 29, 2023 (Successor) and December 30, 2022 (Predecessor), respectively. The Company has insurance contracts that serve as collateral for certain of the Company's non-U.S. pension plan benefits. These insurance contracts totaled $7.3 million and $7.3 million as of December 29, 2023 (Successor) and December 30, 2022 (Predecessor), respectively. These amounts were included in other assets on the consolidated balance sheets.

Equity Equity

Equity Equity	12 Months Ended
	Dec. 29, 2023
Equity [Abstract]
Stockholders' Equity Note Disclosure	15. Equity Share Repurchases The Predecessor's Board of Directors previously authorized share repurchase programs. Under the previous program, $1,000.0 million was authorized for share repurchase. No shares were repurchased during the period from January 1, 2022 through June 16, 2022 (Predecessor) and fiscal 2021(Predecessor). The March 2017 Repurchase Program was terminated upon the emergence from the 2020 Bankruptcy Proceedings. On September 29, 2022, during the 2022 Annual General Meeting of Shareholders, the Company’s shareholders approved the Predecessor to make market purchases or overseas market purchases of a maximum of 1,317,093 ordinary shares of the Predecessor. No shares were repurchased during the period from June 17, 2022 through December 30, 2022 (Predecessor) or January 1, 2023 through November 14, 2023 (Predecessor). This repurchase program was terminated upon emergence from the 2023 Bankruptcy Proceedings. The Company also repurchases shares from certain employees in order to satisfy employee tax withholding requirements in connection with the vesting of restricted shares. In addition, the Company repurchases shares to settle certain option exercises. The Company spent zero to acquire shares in connection with equity-based awards in all periods.

Share Plans

Share Plans	12 Months Ended
	Dec. 29, 2023
Share-Based Payment Arrangement [Abstract]
Share Plans	16. Share Plans Total share-based compensation cost was zero, $8.9 million, $1.4 million, $1.7 million, and $10.2 million for the period November 15, 2023 through December 29, 2023 (Successor), the period December 31, 2022 through November 14, 2023 (Predecessor), the period June 17, 2022 through December 30, 2022 (Predecessor), the period January 1, 2022 through June 16, 2022 (Predecessor), and fiscal 2021 (Predecessor), respectively. These amounts are generally included within SG&A expenses in the consolidated statements of operations. The Company recognized zero related tax benefits associated with this expense for all periods presented. Stock Compensation Plans On the 2023 Effective Date, all outstanding equity-based awards under the Mallinckrodt Pharmaceuticals Stock and Incentive Plan, as amended and restated effective February 23, 2022, were automatically cancelled without consideration. No awards were granted during the period from November 15, 2023 through December 29, 2023 (Successor). On the 2020 Effective Date, all outstanding equity-based awards under the Mallinckrodt Pharmaceuticals Stock and Incentive Plan, as amended and restated effective February 23, 2022, were automatically cancelled without consideration. A new Mallinckrodt Pharmaceuticals Stock and Incentive Plan became effective on the 2020 Effective Date, which provided for the award of share options, share appreciation rights, annual performance bonuses, long-term performance awards, restricted units, restricted shares, deferred share units, promissory shares and other share-based awards (collectively, "Awards"). The maximum number of common shares to be issued as Awards, subject to adjustment as provided under the terms of the plan was 1.8 million shares. Share options. Share options are granted to purchase the Company's ordinary shares at prices that are equal to the fair market value of the shares on the date the share option is granted. Share options generally vest in equal annual installments over a period of four years and expire ten years after the date of grant. The grant-date fair value of share options, adjusted for estimated forfeitures, is recognized as expense on a straight-line basis over the requisite service period, which is generally the vesting period. Forfeitures are estimated based on historical experience. Share option activity and information was as follows: Share Options Weighted-Average Exercise Price Outstanding as of December 25, 2020 (Predecessor) 6,069,712 35.95 Expired/Forfeited (516,193) 45.63 Outstanding as of December 31, 2021 (Predecessor) 5,553,519 35.05 Expired/Forfeited (5,553,519) 35.05 Outstanding as of June 16, 2022 (Predecessor) — — Restricted share units. Recipients of restricted share units ("RSUs") have no voting rights and receive dividend equivalent units that vest upon the vesting of the related shares. RSUs generally vest in equal annual installments over a period of three years. Restrictions on RSUs lapse upon normal retirement, death or disability of the employee. The grant-date fair value of RSUs, adjusted for estimated forfeitures, is recognized as expense on a straight-line basis over the service period. The fair market value of RSUs granted is determined based on the market value of the Company's shares on the date of grant. RSU activity was as follows: Shares Weighted-Average Non-vested as of December 25, 2020 (Predecessor) 490,671 20.96 Exercised (186,930) 23.43 Expired/Forfeited (60,844) 19.58 Non-vested as of December 31, 2021 (Predecessor) 242,897 19.40 Expired/Forfeited (242,897) 19.40 Non-vested as of June 16, 2022 (Predecessor) — — Non-vested as of June 17, 2022 (Predecessor) — — Granted 890,485 12.03 Non-vested as of December 30, 2022 (Predecessor) 890,485 12.03 Granted 2,089,814 1.18 Exercised (332,604) 12.89 Expired/Forfeited (2,647,695) 3.35 Non-vested as of November 14, 2023 (Predecessor) — — The total fair value of RSU awards granted during the period from December 31, 2022 through November 14, 2023 (Predecessor) was $2.5 million. Performance share units. Similar to recipients of RSUs, recipients of performance share units ("PSUs") have no voting rights and receive dividend equivalent units. The grant-date fair value of PSUs, adjusted for estimated forfeitures, is generally recognized as expense on a straight-line basis from the grant-date through the end of the performance period. The vesting of PSUs and related dividend equivalent units is generally based on various performance metrics and relative total shareholder return (total shareholder return for the Company as compared to total shareholder return of the PSU peer group), measured over a three A portion of the PSUs granted during the period from June 17, 2022 (Predecessor) to December 30, 2022 (Predecessor) and the period from December 31, 2022 to November 14, 2023 (Predecessor) could have been settled in shares and were classified as equity-based awards, and a portion of the PSUs had the ability to be settled in either shares or cash and were classified as liability-based awards. The Company recognized $2.6 million and $0.1 million of equity-based compensation costs during the period from December 31, 2022 (Predecessor) through November 14, 2023 (Predecessor) and the period from June 17, 2022 (Predecessor) through December 30, 2022 (Predecessor), respectively. The fair value of the liability-based awards was measured quarterly and based on the Company's performance. PSU activity was as follows (1) : Shares Weighted-Average Non-vested as of June 17, 2022 (Predecessor) — — Granted 675,821 8.34 Non-vested as of December 30, 2022 (Predecessor) 675,821 8.34 Granted 1,459,493 10.13 Forfeited (2,135,314) 10.36 Non-vested as of November 14, 2023 (Predecessor) — — (1) The number of shares disclosed within this table are at the target number of 100.0%. The Company generally uses the Monte Carlo model to estimate the probability of satisfying the performance criteria and the resulting fair value of PSU awards. The assumptions used in the Monte Carlo model for PSUs granted during the period December 31, 2022 through November 14, 2023 (Predecessor) and the period from June 17, 2022 through December 30, 2022 (Predecessor) were as follows: Period from Period from Expected stock price volatility 40.1 % 38.9 % Peer group stock price volatility 124.7 128.0 Correlation of returns 23.8 24.4

Guarantees

Guarantees	12 Months Ended
	Dec. 29, 2023
Guarantees [Abstract]
Guarantees	17. Guarantees In disposing of assets or businesses, the Company has from time to time provided representations, warranties and indemnities to cover various risks and liabilities, including unknown damage to assets, environmental risks involved in the sale of real estate, liability to investigate and remediate environmental contamination at waste disposal sites and manufacturing facilities, and unidentified tax liabilities related to periods prior to disposition. The Company assesses the probability of potential liabilities related to such representations, warranties and indemnities and adjusts potential liabilities as a result of changes in facts and circumstances. The Company believes, given the information currently available, that the ultimate resolutions will not have a material adverse effect on its financial condition, results of operations and cash flows. In connection with the sale of the Specialty Chemical business (formerly known as Mallinckrodt Baker) in fiscal 2010, the Company agreed to indemnify the purchaser with respect to various matters, including certain environmental, health, safety, tax and other matters. The indemnification obligations relating to certain environmental, health and safety matters have a term of 17 years from the sale, while some of the other indemnification obligations have an indefinite term. The liability relating to all of these indemnification obligations was governed by a contract that was rejected as part of the 2020 Bankruptcy Proceedings and is no longer a liability subsequent to the 2020 Effective Date. The Company was required to pay $30.0 million into an escrow account as collateral to the purchaser. The contract governing the escrow account was assumed in the 2020 Bankruptcy Proceedings. As of December 29, 2023 (Successor) and December 30, 2022 (Predecessor), $20.2 million and $19.3 million, respectively, remained in restricted cash, included in other long-term assets on the consolidated balance sheets. As of December 29, 2023 (Successor), the Company does not expect to make future payments related to these indemnification obligations. As of December 29, 2023 (Successor), the Company had various other letters of credit, guarantees and surety bonds totaling $31.4 million and restricted cash of $42.9 million held in segregated accounts primarily to collateralize surety bonds for the Company's environmental liabilities.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 29, 2023
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	18. Commitments and Contingencies The Company is subject to various legal proceedings and claims, including government investigations, environmental matters, product liability matters, patent infringement claims, antitrust matters, securities class action lawsuits, personal injury claims, employment disputes, contractual and other commercial disputes, and other legal proceedings, all in the ordinary course of business, including those described below. Although it is not feasible to predict the outcome of these matters, the Company believes, unless otherwise indicated below, given the information currently available, that the ultimate resolution of any particular matter, or matters that have the same legal or factual issues, will not have a material adverse effect on its financial condition, results of operations and cash flows. Governmental Proceedings Acthar Gel-Related Matters SEC Subpoena. In August 2019, the Company received a subpoena from the SEC for documents related to the Company's disclosure of its dispute with the HHS and CMS (together with the HHS, the "Agency") concerning the base date average manufacturer price for Acthar Gel under the Medicaid Drug Rebate Program, which was also the subject of litigation that the Company filed against the Agency. The SEC issued subsequent subpoenas on January 7, 2022 and September 28, 2022, requesting additional documents from the Company. In connection with the investigation, on January 13, 2023, the SEC staff issued Wells Notices to the Company and individuals, including certain of its current and former executive officers, who were employed during 2019 (collectively, the "Individuals"). The notices indicate that the SEC staff has made a preliminary determination to recommend that the SEC file an enforcement action against the Company that would allege violations of the federal securities laws, and against the Individuals that would allege violations of the federal securities laws and/or aiding and abetting violations of the federal securities laws. The Wells Notices indicated that the SEC staff would allege, among other things, that (a) the Company improperly omitted to disclose the dispute with the Agency prior to the litigation filed by the Company in federal court on May 21, 2019, and (b) the Company’s disclosure of the civil investigative demand received from the U.S. Attorney’s Office for the District of Massachusetts in January 2019 ("Boston CID") should have stated that the Boston CID related to the Company’s dispute with the Agency. On November 30, 2023, the Company reached an agreement with the SEC to resolve the SEC staff’s investigation into the Company’s disclosures relating to (a) the dispute with the Agency and (b) the Boston CID. Specifically, the Company consented to the entry of an Order Instituting Cease-And-Desist Proceedings Pursuant to Section 8A of the Securities Act and Section 21C of the Exchange Act, Making Findings, and Imposing a Cease-And-Desist Order ("Order"). The Order included findings by the SEC that are neither admitted nor denied by the Company and directed Mallinckrodt to cease and desist from committing or causing any violations and any future violations of Sections 17(a)(2) and 17(a)(3) of the Securities Act of 1933, as amended, Sections 13(a), 13(b)(2)(A), and 13(b)(2)(B) of the Exchange Act of 1934, as amended (Exchange Act"), and Exchange Act Rules 12b-20, 13a-1, 13a-13, and 13a-15(a). In addition, the Order requires the Company to retain a compliance consultant ("Consultant") to review the Company’s disclosure controls and procedures relating to collection and assessment of information concerning potential risks, contingencies, trends, and uncertainties, and the implementation and sufficiency of the Company’s internal accounting controls related to GAAP ASC 450. Under the terms of the Order, the Company will implement recommendations of the Consultant. Other Related Matters Florida Civil Investigative Demand. In or around February 2019, the Company received a civil investigative demand ("CID") from the U.S. Attorney's Office for the Middle District of Florida for documents related to alleged payments to healthcare providers in Florida and whether those payments violated the Anti-Kickback Statute. The Company has cooperated with the investigation. Generic Pricing Subpoena. In March 2018, the Company received a grand jury subpoena issued by the U.S. District Court for the EDPA pursuant to which the Antitrust Division of the DOJ is seeking documents regarding generic products and pricing, communications with generic competitors and other related matters. The Company is in the process of responding to this subpoena and intends to cooperate in the investigation. MNK 2011 Inc. (formerly known as Mallinckrodt Inc.) v. U.S. Food and Drug Administration and United States of America. In November 2014, the FDA reclassified the Company's Methylphenidate ER in the Orange Book: Approved Drug Products with Therapeutic Equivalence ("Orange Book"). In November 2014, the Company filed a Complaint in the U.S. District Court for the District of Maryland Greenbelt Division against the FDA and the U.S. ("MD Complaint") for judicial review of the FDA's reclassification. In July 2015, the court granted the FDA's motion to dismiss with respect to three of the five counts in the MD Complaint and granted summary judgment in favor of the FDA with respect to the two remaining counts ("MD Order"). On October 18, 2016, the FDA initiated proceedings, proposing to withdraw approval of the Company's Abbreviated New Drug Application ("ANDA") for Methylphenidate ER. On October 21, 2016, the U.S. Court of Appeals for the Fourth Circuit issued an order placing the Company's appeal of the MD Order in abeyance pending the outcome of the withdrawal proceedings. The parties exchanged documents and in April 2018, the Company filed its submission in support of its position in the withdrawal proceedings. A potential outcome of the withdrawal proceedings is that the Company's Methylphenidate ER products may lose their FDA approval and have to be withdrawn from the market. U.S. Attorney's Office Subpoena. On August 22, 2023, the Company received a grand jury subpoena from the U.S. Attorney's Office for the Western District of Virginia ("USAO") seeking production of data and information for the time period from July 17, 2017 to the present, including information and data relating to the Company's reporting of suspicious orders for controlled substances, chargebacks and other transactions, and communications between the Company and the U.S. Drug Enforcement Administration ("DEA") regarding those issues. The Company's legal representatives discussed the intended scope of the subpoena and initial timeline with the USAO in August and September 2023. On September 27, 2023, the Company received a second grand jury subpoena from the USAO for documents pertaining to financial accounts related to the prior requests. On March 13, 2024, the Company received an additional grand jury subpoena from the USAO requesting additional information regarding financial transactions involving prescription drug products. On October 11, 2023, the Company’s legal representatives met with the USAO to, among other things, share information with the USAO about the operating injunction under which the Company's Specialty Generics segment has been operating since October 2020 and which was agreed to by 50 state and territory attorneys general and entered by the Bankruptcy Court ("operating injunction"). Among other things, the operating injunction provides that Specialty Generics must retain an independent monitor to evaluate and audit compliance with the operating injunction. R. Gil Kerlikowske, former Director of the Office of National Drug Control Policy and former Commissioner of U.S. Customs and Border Protection, currently serves as the monitor and issues periodic reports on Specialty Generics' compliance program, which can be found on the Company's web site at https://www.mallinckrodt.com/corporate-responsibility/corporate-compliance/. The Company believes that Specialty Generics is in compliance with its obligations through its industry-leading compliance program for controlled substances. Prior to the existing operating injunction, Specialty Generics operated under a compliance-related memorandum of understanding with DEA established in July 2017 that expired in July 2020. The Company is in the process of responding to the subpoenas and intends to cooperate in the investigation. The Company cannot predict the eventual scope, duration or outcome of the investigation at this time. Patent Litigation Branded Products. The Company will continue to vigorously enforce its intellectual property rights relating to its Branded products to prevent the marketing of infringing generic or competing products prior to the expiration of patents covering those products, which, if unsuccessful, could adversely affect the Company's ability to successfully maximize the value of individual Branded products and have an adverse effect on its financial condition, results of operations and cash flows. In the case of litigation filed against potential generic or competing products to Company's Branded products, those litigation matters can either be settled or the litigation pursued through a trial and any potential appeals of the lower court decision. Generic Products. The Company continues to pursue development of a portfolio of generic products, some of which require submission of a Paragraph IV certification against patents listed in the FDA's Orange Book for the Branded product asserting that the Company's proposed generic product does not infringe and/or the Orange Book patent(s) are invalid and/or unenforceable. In the case of litigation filed against Company for such potential generic products, those litigation matters can either be settled or the litigation pursued through a trial and any potential appeals of the lower court decision in order to successfully launch those generic products in the future. Mallinckrodt Pharmaceuticals Ireland Limited et al. v. Airgas Therapeutics LLC et al. On December 30, 2022, the Company initiated litigation against Airgas Therapeutics, LLC, Airgas USA LLC, and Air Liquide S.A. (collectively "Airgas") in the District of Delaware following notice from Airgas of its abbreviated new drug application ("ANDA") submission seeking approval from the FDA for a generic version of INOmax ® (nitric oxide) gas, for inhalation ("INOmax"). Airgas's ANDA received final approval from the FDA in July 2023, and according to Airgas' counsel, the original ANDA was filed in April 2011. The case is at an early stage and discovery is ongoing. In October 2023, the parties completed briefing on the Company’s motion for preliminary injunction seeking to prevent defendants Airgas Therapeutics LLC and Airgas USA LLC from infringing the Company’s U.S. patents during the pendency of the litigation; no hearing date has been scheduled at this time. On February 12, 2024, the court entered stipulations of consent for filing of an amended complaint. On March 22, 2024, the court granted Air Liquide S.A.’s motion to dismiss. AirGas Therapeutics, LLC and AirGas USA LLC remain parties to the litigation. The court set a trial date of September 8, 2025. Many of the patents asserted against Airgas were previously asserted in the District of Delaware against Praxair Distribution, Inc. and Praxair, Inc. (collectively "Praxair") in 2015 and 2016 following Praxair's submissions with FDA seeking approval for a nitric oxide drug product and delivery system. The litigation against Praxair resulted in Praxair's launch of a competitive nitric oxide product. The Company continues to develop and pursue patent protection of next generation nitric oxide delivery systems and additional uses of nitric oxide and intends to vigorously enforce its intellectual property rights against any parties that may seek to market a generic version of the Company's INOmax product and/or next generation delivery systems. Amitiza Patent Challenges . The Company was granted numerous Japanese patents related to Amitiza and its use. In October 2023, the Company received two notifications from the Japan Patent Office ("JPO") that Sawai Pharmaceutical Co., Ltd. has filed two invalidation proceedings against two patent term extension ("PTE") registrations against JP Patent No. 4332353 issued to the Company that cover Amitiza and its use in Japan. In December 2023, the Company received notification that a new invalidation trial has been filed with the JPO against JP Patent Appln. No. 2002-586947 by Sawai Pharmaceutical Co., Ltd. The process is at an early stage. The Company believes that its patents and PTE registrations are valid, and the Company will vigorously defend its patents and PTE registrations. In January 2024, the Company received notification of a new invalidation trial against the Amitiza PTE application as to JP Patent Appln. No. 2002-586947 filed by Towa Pharmaceutical Co., Ltd. that covers Amitiza and its use in Japan. This process is at an early stage. The Company believes that this PTE registration is valid, and the Company will vigorously defend its PTE registrations. Commercial and Securities Litigation Putative Class Action Securities Litigation (Continental General). On July 7, 2023, a putative class action lawsuit was filed against the Company, its Chief Executive Officer ("CEO") Sigurdur Olafsson, its Chief Financial Officer ("CFO") Bryan Reasons, and the Chairman of the Board, Paul Bisaro, in the U.S. District Court for the Southern District of New Jersey, captioned Continental General Insurance Company and Percy Rockdale, LLC v. Mallinckrodt plc et al., No. 23-cv-03662. The complaint purports to be brought on behalf of all persons who purchased or otherwise acquired Mallinckrodt's securities between June 17, 2022 and June 14, 2023. The lawsuit generally alleges that the defendants made false and misleading statements in violation of Sections 10(b) and 20(a) of the Securities Exchange Act of 1934, as amended, and Rule 10b-5 promulgated thereunder related to the Company’s business, operations, and prospects, including its financial strength, its ability to timely make certain payments related to Mallinckrodt’s Opioid-Related Litigation Settlement and the risk of additional filings for bankruptcy protection. The lawsuit seeks monetary damages in an unspecified amount. A lead plaintiff was designated by the court on September 10, 2023. On December 26, 2023, an amended complaint was filed by the lead plaintiff against Olafsson, Reasons, and Bisaro ("Individual Defendants"). As to the Company, any liability to the plaintiffs in this matter was discharged upon emergence from the 2023 Bankruptcy Proceedings. The Individual Defendants filed a motion to dismiss on February 26, 2024. Acument Global . In May 2019, Acument Global Technologies, Inc. ("Acument"), filed a non-class complaint against the Company and other defendants in Tennessee state court, captioned as Acument Global Technologies, Inc., v. Mallinckrodt ARD Inc., et al., alleging violations of Tennessee Consumer Protection Laws, unjust enrichment, fraud and conspiracy to defraud. In February 2020, the court granted-in-part and denied-in-part the Company's motion to dismiss. While the court dismissed Acument's fraud-based claims and its claim under the Tennessee Consumer Protection Act, the court ruled that the antitrust and unjust enrichment claims may proceed. Following lifting of the automatic stay of this litigation pursuant to Section 362 of the Bankruptcy Code, on September 29, 2022, the court remanded the case to state court. On October 31, 2023, the state court granted the plaintiff’s voluntary motion to dismiss the Company from the case. Local 542. In May 2018, the International Union of Operating Engineers ("IUOE") Local 542 filed a non-class complaint against the Company and other defendants in Pennsylvania state court alleging improper pricing and distribution of Acthar Gel, in violation of Pennsylvania's Unfair Trade Practices and Consumer Protection Law, aiding and abetting, unjust enrichment and negligent misrepresentation captioned as Int'l Union of Operating Engineers Local 542 v. Mallinckrodt ARD Inc., et al. Plaintiff filed an amended complaint in August 2018, the Company's objections to which were denied by the court. In January 2021, the Company removed this case to the EDPA. In March 2021, the EDPA granted the Company's motion to transfer the case to the U.S. District Court for the District of Delaware ("District of Delaware") and denied without prejudice Local 542's motion to remand the case to state court. In June 2021, the District of Delaware referred this case to the Bankruptcy Court in Delaware. On November 17, 2022, Local 542 filed a motion to withdraw the reference to the District Court, and the case was transferred back to the District of Delaware at Case No. 22-cv-01502. On December 22, 2022, Local 542 filed a request for the motion to withdraw the reference to be decided by the EDPA and to permit remand to state court. On December 28, 2022, the case was assigned to Judge Ambro of the United States Court of Appeals for the Third Circuit due to related cases. On June 27, 2023, the District of Delaware entered an order to withdraw reference of the action to the Delaware Bankruptcy Court and to transfer the case back to the EDPA in order to be remanded to state court. On January 9, 2024, the Court of Common Please entered an order marking the claims against the Mallinckrodt defendants "discontinued and ended without prejudice." Generic Pharmaceutical Antitrust Multi-District Litigation. In August 2016, a multi-district litigation ("MDL") was established in the EDPA relating to allegations of antitrust violations with respect to generic pharmaceutical pricing ("Generic Pricing MDL"). Plaintiffs in the Generic Pricing MDL, captioned In re: Generic Pharmaceuticals Pricing Antitrust Litigation , allege a conspiracy of price-fixing and customer allocation among generic drug manufacturers beginning in or around July 2009. The Generic Pricing MDL includes lawsuits against the Company and dozens of other pharmaceutical companies, including a complaint filed by Attorneys General for 51 States, Territories and the District of Columbia seeking monetary damages and injunctive relief. While the Company is not subject to monetary damages in connection with these matters as a result of the 2023 Plan and vigorously disagrees with the plaintiffs' characterization of the facts and law, the Company is not able to reasonably estimate whether any injunctive relief will be granted, and if granted, whether it will materially impact the Company's financial position or operations; the Company does not intend to provide further disclosure unless this assessment changes. Environmental Remediation and Litigation Proceedings The Company is involved in various stages of investigation and cleanup related to environmental remediation matters at a number of sites, including as described below. The ultimate cost of site cleanup and timing of future cash outlays is difficult to predict, given the uncertainties regarding the extent of the required cleanup, the interpretation of applicable laws and regulations and alternative cleanup methods. The Company concluded that, as of December 29, 2023 (Successor), it was probable that it would incur remediation costs in the range of $17.7 million to $47.9 million. The Company also concluded that, as of December 29, 2023 (Successor), the best estimate within this range was $36.1 million, of which $1.0 million was included in accrued and other current liabilities environmental liabilities Lower Passaic River, New Jersey . The Company and approximately 70 other companies ("Cooperating Parties Group" or "CPG") are parties to a May 2007 Administrative Order on Consent with the Environmental Protection Agency ("EPA") to perform a remedial investigation and feasibility study ("RI/FS") of the 17-mile stretch known as the Lower Passaic River Study Area ("River"). The Company's potential liability stems from former operations at Lodi and Belleville, New Jersey (the "Lodi facility" and the "Belleville facility" respectively). In April 2014, the EPA issued a revised Focused Feasibility Study ("FFS"), with remedial alternatives to address cleanup of the lower 8-mile stretch of the River. The EPA estimated that the cost for the remediation alternatives ranged from $365.0 million to $3.2 billion and the EPA's preferred approach had an estimated cost of $1.7 billion. In April 2015, the CPG presented a draft of the RI/FS of the River to the EPA that included alternative remedial actions for the entire 17-mile stretch of the River. In March 2016, the EPA issued the Record of Decision ("ROD(s)") for the lower 8 miles of the River with a slight modification on its preferred approach and a revised estimated cost of $1.38 billion. In October 2016, the EPA announced that Occidental Chemicals Corporation had entered into an agreement to develop the remedial design. In August 2018, the EPA finalized a buyout offer of $280,600 with the Company, limited to its former Lodi facility, for the lower 8 miles of the River. In September 2021, the EPA issued the ROD for the upper 9 miles of the River selecting source control as the remedy for the upper 9 miles with an estimated cost of $441.0 million. In September 2022, the Company entered into a conditional $0.3 million Early Cash-Out Consent Decree ("CD") with the EPA as a buyout for its portion of the upper part of the River related to its former Lodi facility; finalization of the CD is subject to the EPA approval following the public comment period that was extended until a September 22, 2023 court hearing to determine whether the court will hold a Fairness Hearing or whether the EPA will finalize and approve the conditional CD. On October 16, 2023, the court granted the EPA's request for a sixty-day extension, until November 21, 2023, to notify the Court regarding whether it plans to move forward with the conditional CD. The comment period resulted in a modification to the CD by USEPA which includes a cost reopener of $3.7 billion to the covenant not to sue. The United States filed the modified CD on January 17, 2024, and a motion for entry and response to comments was filed on January 31, 2024. The portion of the liability related to the Belleville facility was discharged against the Company as a result of the 2020 Plan. Any reserves associated with this contingency were included in LSTC as of June 16, 2022, and any related liabilities were discharged under the Bankruptcy Code. The portion of the liability related to the Lodi facility remains a part of the reserve until the CD is lodged. As of December 29, 2023 (Successor), the Company estimated that its remaining liability related to the River was $21.0 million, which was included within environmental liabilities on the consolidated balance sheet as of December 29, 2023 (Successor). Despite the issuance of the revised FFS and the RODs for both the lower and upper River by the EPA, the RI/FS by the CPG, and the conditional CD by the EPA, there are many uncertainties associated with the final agreed-upon remediation, potential future liabilities and the Company's allocable share of the remediation. Given those uncertainties, the amounts accrued may not be indicative of the amounts for which the Company may be ultimately responsible and will be refined as the remediation progresses. Bankruptcy Litigation and Appeals First Lien Noteholder Matters. The 2020 Plan reinstated the 2025 First Lien Notes in an aggregate principal amount of $495.0 million and the note documents relating thereto. Certain holders of the 2025 First Lien Notes and the trustee in respect thereof (collectively, "Noteholder Parties"), objected to the reinstatement, arguing, among other things, that the Company was required to pay a significant make-whole premium as a condition to reinstatement of the 2025 First Lien Notes. In the course of confirming the 2020 Plan, the Bankruptcy Court overruled these objections. On March 30, 2022, the Noteholder Parties appealed the confirmation order's approval of the reinstatement of the 2025 First Lien Notes to the United States District Court for the District of Delaware ("District Court"). The Company and the 2025 First Lien Notes trustee reached an agreement to hold the trustee's appeal in abeyance, to be determined by the result of the holders' appeals, subject to certain conditions, which was approved by the District Court. Briefing on the merits of the Noteholder Parties' appeals was completed on July 1, 2022. On the same date, the Company moved to dismiss the Noteholder Parties' appeals as equitably moot. Briefing on the motion was completed on August 5, 2022 and supplemental declarations were filed in the appeal. Oral argument was held on the Noteholder Parties' appeals on May 5, 2023, and the District Court took the matter under advisement. As part of the 2023 restructuring support agreement ("2023 RSA"), certain holders including holders representing a substantial majority of the 2025 First Lien Notes ("Ad Hoc First Lien Notes Group") agreed to settle these appeals through the 2023 Plan. Among other provisions, the 2023 Plan incorporates the 2025 First Lien Notes Makewhole Settlement (as defined in the 2023 Plan), which comprises the allowance of a 2025 First Lien Notes Makewhole Amount Claim (as defined in the 2023 Plan) in a stipulated amount of $14.9 million (or 3.0% of the principal amount of the 2025 First Lien Notes). In exchange, the Ad Hoc First Lien Notes Group agreed to dismiss its appeal, and to cause the trustee to dismiss its companion appeal, upon the 2023 Effective Date. On August 23, 2023, the parties wrote to the District Court to outline the settlement and request that the appeals be held in abeyance pending the confirmation of the amended 2023 Plan. On August 23, 2023, the District Court entered an order stating that it would defer indefinitely issuing a decision in the appeal, but reserving the right to file an opinion and order at any later time prior to the filing of a stipulated dismissal of the appeals. On August 28, 2023, Columbus Hill Capital Management, L.P., a Noteholder Party that had filed a separate appeal, agreed to dismiss its appeal because it had sold the entirety of its position in the 2025 First Lien Notes. As further described herein, the 2023 Plan, including the 2025 First Lien Notes Makewhole Settlement, was confirmed by the Bankruptcy Court on October 10, 2023. The appeal of the Ad Hoc First Lien Notes Group was resolved under the 2023 Plan, and the parties thereto filed an agreement to voluntarily dismiss the appeal on December 5, 2023. Sanofi. On October 13, 2021, in the Company's 2020 Chapter 11 Cases, sanofi-aventis U.S. LLC ("Sanofi") filed a motion asking the Bankruptcy Court for an order determining that, under the Bankruptcy Code, the Company could not discharge certain alleged royalty obligations owed to Sanofi under an asset purchase agreement through which the Company acquired certain intellectual property from Sanofi's predecessor ("Sanofi Motion"). On November 4, 2021, the Bankruptcy Court denied the Sanofi Motion and ordered that any royalty obligations allegedly owed to Sanofi constitute prepetition unsecured claims that may be discharged under the Bankruptcy Code. On November 19, 2021, Sanofi appealed the Bankruptcy Court's ruling of the Sanofi Motion to the District Court. Briefing was completed on March 10, 2022 and the District Court affirmed on December 21, 2022, for which Sanofi filed a notice of appeal to the Third Circuit Court of Appeals on January 17, 2023. While the appeal has been fully briefed and the Third Circuit heard oral argument on December 11, 2023, the Third Circuit has yet to rule on the appeal. Stratatech. Consummation of the 2020 Plan discharged the Company's liability with respect to certain contingent consideration provided to the prior securityholders of Stratatech Corporation ("Stratatech"). However, Russell Smestad, as the representative of these securityholders, has filed a motion in the Bankruptcy Court for an order either (i) granting allowance and immediate payment of an administrative expense claim in the amount of the liability of $20 million or (ii) finding that the claim was not susceptible to discharge and should be paid in full. The Company believes that the securityholders’ motion is without merit and intends to vigorously oppose it. Discovery was substantially complete prior to the 2023 Bankruptcy Proceedings. Litigation of the securityholders’ motion was stayed automatically when the Company commenced the 2023 Bankruptcy Proceedings on August 28, 2023. Since the 2023 Debtors emerged from the 2023 Bankruptcy Proceedings on November 14, 2023, the Court set a schedule to complete discovery and other pre-hearing procedures. No hearing date before the Bankruptcy Court has been set. Opioid-Related Litigation Settlement On June 15, 2023, the Company, certain subsidiaries of the Company and the Trust entered into Amendment No. 1 ("Amendment") to the Opioid Deferred Cash Payments Agreement, which was entered into in connection with the 2020 Plan. The Amendment extended to June 23, 2023, from June 16, 2023, the date on which the $200.0 million installment payment with respect to the Opioid Deferred Cash Payment was required to be made to the Trust. Pursuant to the Amendment, the Trust subsequently provided several additional written notices that had the effect of extending the due date of the Opioid Deferred Cash Payment to August 15, 2023. In connection with entry into the 2023 RSA, the Company and the Trust entered into a final amendment to the Opioid Deferred Cash Payments Agreement, which provided that the Company's prior obligation to pay all remaining Opioid-Related Litigation Settlement payment obligations (including the Opioid Deferred Cash Payment) was permanently eliminated subject to the Company (a) making a $250.0 million payment to the Trust prior to the commencement of the 2023 Bankruptcy Proceedings (which was made on August 24, 2023) and (b) entering into the CVR Agreement to receive a payment (in cash or, at the Company's option subject to certain conditions, shares of the Company's equity) equal to the value of 5% of the Company's total outstanding equity (subject to certain dilution) less the exercise price, which is based on a total enterprise value of $3.776 billion less funded debt at emergence plus any excess cash at emergence after the emergence-date cash sweep contemplated by the 2023 RSA. Additionally, the 2023 Debtors' non-monetary obligations to the Trust were generally preserved, including the compliance-related operating injunction and the cooperation agreement (as amended). Other Matters The Company is a defendant in a number of other pending legal proceedings relating to present and former operations, acquisitions and dispositions. The Company does not expect the outcome of these proceedings, either individually or in the aggregate, to have a material adverse effect on its financial condition, results of operations and cash flows.

Financial Instruments and Fair

Financial Instruments and Fair Value Measurements	12 Months Ended
	Dec. 29, 2023
Fair Value Disclosures [Abstract]
Financial Instruments and Fair Value Measurements	19. Financial Instruments and Fair Value Measurements Fair value is defined as the exit price that would be received from the sale of an asset or paid to transfer a liability, using assumptions that market participants would use in pricing an asset or liability. The fair value guidance establishes a three-level fair value hierarchy, which maximizes the use of observable inputs and minimizes the use of unobservable inputs used in measuring fair value. The levels within the hierarchy are as follows: Level 1— observable inputs such as quoted prices in active markets for identical assets or liabilities; Level 2— significant other observable inputs that are observable either directly or indirectly; and Level 3— significant unobservable inputs in which there is little or no market data, which requires the Company to develop its own assumptions. The following tables provide a summary of the significant assets and liabilities that are measured at fair value on a recurring basis at the end of each period: December 29, 2023 (Successor) Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs Assets: Debt and equity securities held in rabbi trusts $ 43.3 $ 29.1 $ 14.2 $ — Equity securities 28.9 28.9 — — Interest rate cap 12.9 — — 12.9 $ 85.1 $ 58.0 $ 14.2 $ 12.9 Liabilities: Debt derivative liabilities $ 15.1 $ — $ — $ 15.1 Deferred compensation liabilities 21.0 — 21.0 — Contingent consideration liabilities 14.7 — — 14.7 $ 50.8 $ — $ 21.0 $ 29.8 December 30, 2022 (Predecessor) Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs Assets: Debt and equity securities held in rabbi trusts $ 36.6 $ 24.8 $ 11.8 $ — Equity securities 25.5 25.5 — — $ 62.1 $ 50.3 $ 11.8 $ — Liabilities: Deferred compensation liabilities $ 26.0 $ — $ 26.0 $ — Contingent consideration liabilities 7.3 — — 7.3 $ 33.3 $ — $ 26.0 $ 7.3 Debt and equity securities held in rabbi trusts . Debt securities held in rabbi trusts primarily consist of U.S. government and agency securities and corporate bonds. When quoted prices are available in an active market, the investments are classified as level 1. When quoted market prices for a security are not available in an active market, they are classified as level 2. Equity securities held in rabbi trusts primarily consist of U.S. common stocks, which are valued using quoted market prices reported on nationally recognized securities exchanges. Equity securities . Equity securities consist of shares in Silence Therapeutics plc and Panbela Therapeutics, Inc. for which quoted prices are available in an active market; therefore, these investments are classified as level 1 and are valued based on quoted market prices reported on internationally recognized securities exchanges. During the period November 15, 2023 through December 29, 2023 (Successor), the period June 17, 2022 through December 30, 2022 (Predecessor), and fiscal 2021 (Predecessor), the Company recognized an unrealized gain of $13.5 million, $9.2 million, and $4.7 million, respectively and during the period December 31, 2022 through November 14, 2023 (Predecessor) and the period January 1, 2022 through June 16, 2022 (Predecessor), the Company recognized an unrealized loss of $10.1 million and $22.2 million, respectively, related to our investments within other income (expense), net in the consolidated statements of operations. Interest rate cap . The Company is exposed to interest rate risk on its variable-rate debt. During the three months ended March 31, 2023 (Predecessor), the Company entered into an interest rate cap agreement, which serves to reduce the volatility on future interest expense cash outflows. The interest rate cap agreement has a total notional value of $860.0 million with an upfront premium of $20.0 million and provides the Company with interest rate protection (i) for the period March 16, 2023 through July 19, 2023 to the extent that the one-month LIBOR exceeds 4.65%, and (ii) for the period July 20, 2023 through March 26, 2026 to the extent that the one-month SOFR exceeds 3.84%. During the period from March 16, 2023 to November 14, 2023 (Predecessor), the interest rate cap agreement qualified as a cash flow hedge. The premium paid was recognized in income on a rational basis, and changes in the fair value of the interest rate cap were recorded within accumulated other comprehensive income ("AOCI") and were subsequently reclassed into interest expense in the period when the hedged interest affects earnings. Upon adoption of fresh-start accounting, the Company reassessed the interest rate cap and elected to not apply hedge accounting. As such, during the Successor period, the interest rate cap agreement was not accounted for as a cash flow hedge and the changes in fair value of the interest rate cap were recorded within other income (expense) in the consolidated statement of operations. The fair value of the interest rate cap is included in other assets on the Company’s consolidated balance sheet as of December 29, 2023 (Successor). The Company elected to use the income approach to value the interest rate cap derivative using observable Level 2 market expectations at the measurement date and standard valuation techniques to convert future amounts to a single present amount (discounted) reflecting current market expectations about those future amounts. Level 2 inputs for derivative valuations are limited to quoted prices for similar assets or liabilities in active markets (specifically futures contracts) and inputs other than quoted prices that are observable such as LIBOR or SOFR rate curves, futures and volatilities. Mid-market pricing is used as a practical expedient in the fair value measurements. During the period from December 31, 2022 through November 14, 2023 (Predecessor), the Company recognized an unrealized gain of $5.7 million within AOCI with a gain of $0.7 million being reclassified into earnings as a component of interest expense, net. During the period from November 15, 2023 to December 29, 2023 (Successor), the Company recognized an $8.4 million unrealized loss in other income (expense) related to the changes in fair value of the interest rate cap. The cash payment of the $20.0 million premium and other corresponding activity related to the interest rate cap were reflected as cash flows from operating activities in the consolidated statement of cash flows for the period December 31, 2022 to November 14, 2023 (Predecessor). Debt derivative liabilities. The debt derivative liabilities related to the Company's First and Second-Out Takeback Term Loans and Takeback Notes are measured using a 'with and without' valuation model to compare the fair values of each debt instrument including the identified embedded derivative feature. The "with" value corresponds to the fair value of each instrument assuming mandatory prepayment upon an asset sale. The "without" value corresponds to the fair value of each instrument assuming no mandatory prepayment upon an asset sale These derivative liabilities are classified as level 3 and the fair value of the debt instruments including the embedded derivative features were determined using the Black-Derman-Toy model based on three potential scenarios included in the tables below which includes significant unobservable inputs. The estimated settlement value of each scenario, which would include any required applicable premium (see Note 13), is then discounted to present value using a discount rate that is a 3.08% and 4.58% credit spread for the First and Second-Out Takeback Term Loans, respectively, plus the U.S. treasury yield commensurate with the cash flow payment date. The applicable premium estimates were calculated at each mandatory prepayment event date in accordance with the contractual definition and were based, in part, on subjective assumptions. These subjective assumptions relate to scenario-related proceeds from an asset sale, inclusive of estimated transaction fees and related taxes. The debt derivative liability is recorded at fair value, with the changes in fair value reported within earnings. The debt derivative liability was $15.1 million as of November 14, 2023 (Predecessor) and December 29, 2023 (Successor) and was recorded within accrued and other current liabilities within the consolidated balance sheet as of December 29, 2023 (Successor). Significant assumptions utilized in the determination of the fair value are as follows: First and Second-Out Takeback Term Loans: Input Scenario 1 Scenario 2 Scenario 3 Remaining term (years) 5 5 5 Maturity Date November 14, 2028 November 14, 2028 November 14, 2028 Coupon Rate 7.50% - 9.50% + SOFR 7.50% - 9.50% + SOFR 7.50% - 9.50% + SOFR Probability of mandatory prepayment event before November 2025 (1) 25.00% 25.00% 6.25% Estimated timing of mandatory prepayment event before November 2025 (1) August 2024 December 2024 August and December 2024 (1) Represents a significant unobservable input Takeback Notes: Input Scenario 1 Scenario 2 Scenario 3 Remaining term (years) 5 5 5 Maturity Date November 14, 2028 November 14, 2028 November 14, 2028 Coupon Rate 14.75% 14.75% 14.75% Probability of mandatory prepayment event before November 2025 (1) 25.00% 25.00% 6.25% Estimated timing of mandatory prepayment event before November 2025 (1) August 2024 December 2024 August and December 2024 (1) Represents a significant unobservable input Deferred compensation liabilities. The Company maintains a non-qualified deferred compensation plan in the U.S., which permits eligible employees of the Company to defer a portion of their compensation. A recordkeeping account is set up for each participant and the participant chooses from a variety of funds for the deemed investment of their accounts. The recordkeeping accounts generally correspond to the funds offered in the Company's U.S. tax-qualified defined contribution retirement plan and the account balance fluctuates with the investment returns on those funds. Contingent consideration liabilities. In accordance with the 2020 Plan and the 2020 Scheme of Arrangement, the Company will provide consideration for the Terlivaz CVR primarily in the form of the achievement of a cumulative net sales milestone. The Company assesses the likelihood and timing of making such payments at each balance sheet date. The fair value of the contingent payment was measured based on the net present value of a probability-weighted assessment. The Company determined the fair value of the Terlivaz CVR as of December 29, 2023 (Successor) and December 30, 2022 (Predecessor) to be $14.7 million and $7.3 million, respectively. All contingent consideration liabilities were classified within other liabilities in the consolidated balance sheets as of December 29, 2023 (Successor) and December 30, 2022 (Predecessor), respectively. The following table summarizes activity for contingent consideration: Balance as of December 30, 2022 (Predecessor) $ 7.3 Fair value adjustments (7.2) Fresh-start adjustment 14.9 Balance as of November 14, 2023 (Predecessor) $ 15.0 Balance as of November 15, 2023 (Successor) $ 15.0 Fair value adjustments (0.3) Balance as of December 29, 2023 (Successor) $ 14.7 Financial Instruments Not Measured at Fair Value The following methods and assumptions were used by the Company in estimating fair values for financial instruments not measured at fair value as of December 29, 2023 (Successor) and December 30, 2022 (Predecessor): • The carrying amounts of cash and cash equivalents, accounts receivable, accounts payable and the majority of other current assets and liabilities approximate fair value because of their short-term nature. The Company classifies cash on hand and deposits in banks, including commercial paper, money market accounts and other investments it may hold from time to time, with an original maturity of three months or less, as cash and cash equivalents (level 1). The fair value of restricted cash was equivalent to its carrying value of $80.7 million and $57.2 million as of December 29, 2023 (Successor) and December 30, 2022 (Predecessor), (level 1), respectively. Included within the balance as of the 2023 Effective Date was $24.0 million related to the funding of a professional fee escrow account upon emergence from the 2023 Bankruptcy Proceedings. Refer to Note 3 for further information. As of December 29, 2023 (Successor), the professional fee escrow balance was $17.6 million. • The Company's life insurance contracts are carried at cash surrender value, which is based on the present value of future cash flows under the terms of the contracts (level 3). Significant assumptions used in determining the cash surrender value include the amount and timing of future cash flows, interest rates and mortality charges. The fair value of these contracts approximates the carrying value of $45.3 million and $46.7 million as of December 29, 2023 (Successor) and December 30, 2022 (Predecessor), respectively. These contracts are included in other assets on the consolidated balance sheets. • Successor debt. The Company's Takeback Notes and receivables securitization facility are classified as level 1, as quoted prices are available in an active market for these notes. Since quoted market prices for the Company's Takeback Term Loans are not available in an active market, they are classified as level 2 for purposes of developing an estimate of fair value. Predecessor debt. The Company's First Lien Notes and receivables financing facility are classified as level 1, as quoted prices are available in an active market for these notes. Since quoted market prices for the Company's term loans are not available in an active market, they are classified as level 2 for purposes of developing an estimate of fair value. Successor Predecessor December 29, 2023 December 30, 2022 Carrying Fair Carrying Fair Level 1: 14.75% Second-Out Takeback Notes due November 2028 $ 836.4 $ 844.4 $ — $ — 10.00% first lien senior secured notes due April 2025 — — 475.9 425.9 10.00% second lien senior secured notes due April 2025 — — 242.2 216.8 11.50% first lien senior secured notes due December 2028 — — 650.0 552.6 10.00% second lien senior secured notes due June 2029 — — 175.5 176.7 Level 2: First-Out Takeback Term Loan Due November 2028 243.4 232.8 — — Second-Out Takeback Term Loan Due November 2028 685.5 654.0 — — 2017 Replacement Term loan due September 2027 — — 1,222.1 1,037.8 2018 Replacement Term loan due September 2027 — — 326.9 274.8 Total Debt $ 1,765.3 $ 1,731.2 $ 3,092.6 $ 2,684.6 Concentration of Credit and Other Risks Financial instruments that potentially subject the Company to concentrations of credit risk primarily consist of accounts receivable. The Company generally does not require collateral from customers. A portion of the Company's accounts receivable outside the U.S. includes sales to government-owned or supported healthcare systems in several countries, which are subject to payment delays. Payment is dependent upon the financial stability and creditworthiness of those countries' national economies. The following table shows net sales attributable to distributors that accounted for 10.0% or more of the Company's total segment net sales: Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 FFF Enterprises, Inc. 23.1 % 22.3 % 26.1 % 11.8 % *% McKesson Corporation 10.8 * * * * AmerisourceBergen Corporation * 10.0 * * * CuraScript, Inc. * * * 15.6 26.1 * Net sales to this distributor were less than 10.0% of total net sales during the respective periods presented above. The following table shows accounts receivable attributable to distributors that accounted for 10.0% or more of the Company's gross accounts receivable at the end of each period: Successor Predecessor December 29, December 30, AmerisourceBergen Corporation 24.2% 23.3% McKesson Corporation 20.0 17.3 FFF Enterprises, Inc. * 16.2 * Accounts receivable attributable to this distributor was less than 10.0% of total gross accounts receivable at the end of the respective period presented above. The following table shows net sales attributable to products that accounted for 10.0% or more of the Company's total segment net sales: Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 Acthar Gel 23.5 % 22.7 % 28.3 % 25.4 % 26.9 % INOmax 14.5 16.5 16.7 19.0 20.3 Therakos 16.1 13.6 12.5 12.5 12.1 APAP 13.4 11.4 10.7 11.0 *

Segment and Geographical Data

Segment and Geographical Data	12 Months Ended
	Dec. 29, 2023
Segment Reporting [Abstract]
Segment and Geographical Data	20. Segment and Geographical Data The Company operates in two reportable segments, which are further described below: • Specialty Brands includes innovative specialty pharmaceutical brands; and • Specialty Generics includes niche specialty generic drugs and API(s). Management measures and evaluates the Company's operating segments based on segment net sales and operating income. Management excludes corporate expenses from segment operating income. In addition, certain amounts that management considers to be non-recurring or non-operational are excluded from segment operating income because management and the chief operating decision maker evaluate the operating results of the segments excluding such items. These items may include, but are not limited to, depreciation and amortization, share-based compensation, net restructuring charges, non-restructuring impairment charges and liabilities management and separation costs. Although these amounts are excluded from segment operating income, as applicable, they are included in reported consolidated operating loss and are reflected in the reconciliations presented below. Management manages assets on a total company basis, not by operating segment. The Company's chief operating decision maker does not regularly review any asset information by operating segment and, accordingly, the Company does not report asset information by operating segment. Total assets were approximately $3,733.6 million and $6,013.8 million as of December 29, 2023 (Successor) and December 30, 2022 (Predecessor), respectively. Selected information by reportable segment was as follows: Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 Net sales: Specialty Brands $ 139.8 $ 949.2 $ 682.4 $ 587.1 $ 1,547.0 Specialty Generics 103.2 673.7 357.3 287.5 661.8 Net sales $ 243.0 $ 1,622.9 $ 1,039.7 $ 874.6 $ 2,208.8 Operating loss: Specialty Brands $ 9.0 $ 209.9 $ 113.8 $ 267.2 $ 812.8 Specialty Generics (1) 5.8 156.2 (3.6) 65.3 107.9 Segment operating income 14.8 366.1 110.2 332.5 920.7 Unallocated amounts: Corporate and unallocated expenses (2) (4.0) (45.8) (39.3) (48.2) (129.6) Depreciation and amortization (25.8) (490.3) (347.5) (321.8) (675.8) Share-based compensation — (8.9) (1.4) (1.7) (10.2) Restructuring charges, net — (0.9) (11.1) (9.6) (26.9) Non-restructuring impairment charges (3) (3.8) (179.9) — — (154.9) Liabilities management and separation costs (4) (1.4) (157.7) (21.2) (9.0) (1.2) Opioid-Related Litigation Settlement loss — — — — (125.0) Bad debt expense - customer bankruptcy — — (6.4) — — Operating loss $ (20.2) $ (517.4) $ (316.7) $ (57.8) $ (202.9) Depreciation and amortization: Specialty Brands $ 15.3 $ 455.3 $ 323.6 $ 288.4 $ 597.7 Specialty Generics 10.5 35.0 23.9 33.4 78.1 $ 25.8 $ 490.3 $ 347.5 $ 321.8 $ 675.8 (1) Includes $30.0 million of fresh-start inventory-related expense during the period from June 17, 2022 through December 30, 2022 (Predecessor) primarily driven by the Company's change in accounting estimate. (2) Includes administration expenses and certain compensation, legal, environmental and other costs not charged to the Company's reportable segments. (3) Includes $135.9 million and $154.9 million of impairment charges on intangible assets during the period December 31, 2022 through November 14, 2023 (Predecessor) and fiscal 2021 (Predecessor), respectively, as further described in Note 12, a $44.0 million Acthar Gel inventory write-down to net realizable value during the period December 31, 2022 through November 14, 2023 (Predecessor), and $3.8 million of impairment charges on StrataGraft long-lived assets during the period November 15, 2023 through December 29, 2023 (Successor). (4) Represents costs primarily related to professional fees incurred by the Company (including where the Company is responsible for the fees of third parties) in connection with its evaluation of its financial situation and related discussions with its stakeholders prior to the commencement of the 2023 Bankruptcy Proceedings, expenses incurred related to the severance of certain former executives of the Predecessor as a result of the 2020 Bankruptcy Proceedings, in addition to professional fees and costs incurred as the Company explores potential sales of non-core assets to enable further deleveraging post-emergence. As of the 2023 Petition Date and 2020 Petition Date, professional fees directly related to the 2023 Bankruptcy Proceedings and 2020 Bankruptcy Proceedings, respectively, that were previously reflected as liabilities management and separation costs were classified on a go-forward basis as reorganization items, net until the 2023 Effective Date and the 2020 Effective Date, respectively. Net sales by product family within the Company's reportable segments were as follows: Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 Acthar Gel $ 57.0 $ 368.3 $ 294.1 $ 221.9 $ 593.6 INOmax 35.3 267.9 173.9 165.8 448.5 Therakos 39.1 220.0 130.5 109.6 266.5 Amitiza (1) 5.0 72.0 77.1 81.5 196.9 Terlivaz 2.3 13.3 1.2 — — Other 1.1 7.7 5.6 8.3 41.5 Specialty Brands 139.8 949.2 682.4 587.1 1,547.0 Opioids 31.6 230.7 117.9 88.8 213.2 ADHD 13.5 101.4 28.4 17.5 37.4 Addiction treatment 10.5 55.6 35.0 30.0 68.3 Other 1.6 8.2 6.8 4.9 12.0 Generics 57.2 395.9 188.1 141.2 330.9 Controlled substances 11.6 75.5 47.0 37.6 93.4 APAP 32.5 184.8 111.4 96.5 215.9 Other 1.9 17.5 10.8 12.2 21.6 API 46.0 277.8 169.2 146.3 330.9 Specialty Generics 103.2 673.7 357.3 287.5 661.8 Net Sales $ 243.0 $ 1,622.9 $ 1,039.7 $ 874.6 $ 2,208.8 (1) Amitiza net sales consist of both product and royalty net sales. Selected information by geographic area was as follows: Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 Net sales (1) : U.S. $ 212.8 $ 1,448.9 $ 928.3 $ 784.2 $ 1,991.8 Europe, Middle East and Africa 28.8 157.1 100.4 73.6 181.8 Other 1.4 16.9 11.0 16.8 35.2 Net Sales $ 243.0 $ 1,622.9 $ 1,039.7 $ 874.6 $ 2,208.8 (1) Net sales are attributed to regions based on the location of the entity that records the transaction, none of which relate to the country of Ireland.

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 29, 2023
Subsequent Events [Abstract]
Subsequent Events	21. Subsequent Events StrataGraft On January 4, 2024, the Company committed to a plan to cease commercialization and clinical development and wind down production of its StrataGraft product. The decision to discontinue StrataGraft was made following a slower-than-anticipated commercial uptake of the product and slower-than-anticipated enrollment in clinical trials. The Company is evaluating its next steps with respect to StrataGraft, which could include pursuing a sale, out-license or other strategic arrangement. Employment Agreement and Compensation On February 2, 2024, Mallinckrodt’s indirect subsidiary ST Shared Services LLC entered into a new employment agreement with Sigurdur Olafsson pursuant to which Mr. Olafsson will continue to serve as Mallinckrodt’s President and Chief Executive Officer. On February 2, 2024, consistent with the 2023 Plan, the Successor's Board of Directors adopted the Mallinckrodt Pharmaceuticals 2024 Stock and Incentive Plan and reserved an aggregate of 1,036,649 ordinary shares (subject to adjustment in accordance with the terms of the plan) for the issuance of equity awards thereunder to employees and directors. On February 2, 2024, the Board of Directors adopted a Transaction Incentive Plan intended to compensate designated Mallinckrodt executive officers and members of the Mallinckrodt Board of Directors with bonus payments based on the consummation of qualifying asset sale transactions. Acthar Gel On March 1, 2024, the FDA approved the Acthar Gel Single-Dose Pre-filled SelfJect™ Injector ("SelfJect"), a new delivery device for Acthar Gel for appropriate patients with a range of chronic and acute inflammatory and autoimmune conditions. SelfJect is intended to provide the appropriate subcutaneous dose of Acthar Gel, as prescribed by a healthcare professional, and is designed to help give patients control of their administration. Commitments and Contingencies Certain litigation matters occurred prior to December 29, 2023 (Successor) but had subsequent updates through the date of this report. See further discussion in Note 18.

Schedule II - Valuation and Qua

Schedule II - Valuation and Qualifying Accounts (Notes)	12 Months Ended
	Dec. 29, 2023
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract]
Schedule II - Valuation and Qualifying Accounts	Financial Statement Schedules. The financial statement schedule is included below. All other schedules have been omitted because they are not applicable, not required or the information is included in the financial statements or notes thereto. Schedule II - Valuation and Qualifying Accounts (in millions) Description Balance at Beginning of Period Charged to Costs and Expenses Charged to Other Accounts Deductions Balance at End of Period Allowance for doubtful accounts: Fiscal year ended Period from November 15, 2023 through December 29, 2023 (Successor) $ 5.6 2.9 $ — $ (2.0) $ 6.5 Fiscal year ended Period from December 31, 2022 through November 14, 2023 (Predecessor) 4.4 4.2 — (3.0) 5.6 Fiscal year ended Period from June 17, 2022 through December 30, 2022 (Predecessor) 5.9 0.5 — (2.0) 4.4 Fiscal year ended Period from January 1, 2022 through June 16, 2022 (Predecessor) 4.7 1.2 — — 5.9 Fiscal year ended December 31, 2021 (Predecessor) 4.5 1.2 — (1.0) 4.7 Sales reserve accounts: Fiscal year ended Period from November 15, 2023 through December 29, 2023 (Successor) $ 250.5 $ 182.9 $ — $ (206.0) $ 227.4 Fiscal year ended Period from December 31, 2022 through November 14, 2023 (Predecessor) 294.0 1,422.0 — (1,465.5) 250.5 Fiscal year ended Period from June 17, 2022 through December 30, 2022 (Predecessor) 276.9 848.1 — (831.0) 294.0 Fiscal year ended Period from January 1, 2022 through June 16, 2022 (Predecessor) 272.8 715.7 — (711.6) 276.9 Fiscal year ended December 31, 2021 (Predecessor) 235.4 2,166.0 — (2,128.6) 272.8 Tax valuation allowance: Fiscal year ended Period from November 15, 2023 through December 29, 2023 (Successor) $ 4,584.8 $ (1.1) $ 0.1 $ — 4,583.8 Fiscal year ended Period from December 31, 2022 through November 14, 2023 (Predecessor) 4,992.9 (407.4) (0.7) — 4,584.8 Fiscal year ended Period from June 17, 2022 through December 30, 2022 (Predecessor) 5,129.7 (136.0) (0.8) — 4,992.9 Fiscal year ended Period from January 1, 2022 through June 16, 2022 (Predecessor) 6,344.2 (1,213.5) (1.0) — 5,129.7 Fiscal year ended December 31, 2021 (Predecessor) 6,110.8 233.4 — — 6,344.2

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 29, 2023
Accounting Policies [Abstract]
Revenue Recognition	Revenue Recognition Product Sales Revenue The Company sells its products through independent channels, including direct to retail pharmacies, end user customers and through distributors who resell the products to retail pharmacies, institutions and end user customers, while certain products are sold and distributed directly to hospitals. The Company also enters into arrangements with indirect customers, such as health care providers and payers, wholesalers, government agencies, institutions, managed care organizations and group purchasing organizations to establish contract pricing for certain products that provide for government-mandated and/or privately-negotiated rebates, sales incentives, chargebacks, distribution service agreements fees, fees for services and administration fees and discounts with respect to the purchase of the Company's products. Reserve for Variable Considerations Product sales are recorded at the net sales price (transaction price), which includes estimates of variable consideration for which reserves are established. These reserves result from estimated chargebacks, rebates, product returns and other sales deductions that are offered within contracts between the Company and its customers, health care providers and payers relating to the sale of the Company's products. These reserves are based on the amounts earned or to be claimed on the related sales and are classified as reductions of accounts receivable (if the amount is payable to the customer) or a current liability (if the amount is payable to a party other than a customer). Where appropriate, these estimates take into consideration a range of possible outcomes that are probability-weighted for relevant factors such as the Company's historical experience, estimated future trends, estimated customer inventory levels, current contracted sales terms with customers, level of utilization of the Company's products and other competitive factors. Overall, these reserves reflect the Company's best estimate of the amount of consideration to which it is entitled based on the terms of the contract. The amount of variable consideration that is included in the transaction price may be constrained (reduced) and is included in the net sales price only to the extent that it is probable that a significant reversal in the amount of the cumulative revenue recognized will not occur in a future period. The Company adjusts reserves for chargebacks, rebates, product returns and other sales deductions to reflect differences between estimated and actual experience. Such adjustments impact the amount of net sales recognized in the period of adjustment. Product sales are recognized when the customer obtains control of the Company's product. Control is transferred either at a point in time, generally upon delivery to the customer site, or in the case of certain of the Company's products, over the period in which the customer has access to the product and related services. Revenue recognized over time is based upon either consumption of the product or passage of time based upon the Company's determination of the measure that best aligns with how the obligation is satisfied. The Company's considerations of why such measures provide a faithful depiction of the transfer of its products are as follows: • For those contracts whereby revenue is recognized over time based upon consumption of the product, the Company either has: 1. the right to invoice the customer in an amount that directly corresponds with the value to the customer of the Company's performance to date, for which the practical expedient to recognize in proportion to the amount it has the right to invoice has been applied, or 2. the remaining goods and services to which the customer is entitled is diminished upon consumption. • For those contracts whereby revenue is recognized over time based upon the passage of time, the benefit that the customer receives from unlimited access to the Company's product does not vary, regardless of consumption. As a result, the Company's obligation diminishes with the passage of time; therefore, ratable recognition of the transaction price over the contract period is the measure that best aligns with how the obligation is satisfied. Transaction price allocated to the remaining performance obligations The majority of the Company's contracts have a term of less than one year; and the amount of transaction price allocated to the performance obligations that are unsatisfied at period end is generally expected to be satisfied within one year. Cost to obtain a contract As the majority of the Company's contracts are short-term in nature, sales commissions are generally expensed when incurred as the amortization period would have been less than one year. These costs are recorded within selling, general and administrative expense ("SG&A") in the consolidated statements of operations. For contracts that extend beyond one year, the incremental expense recognition matches the recognition of related revenue. Costs to fulfill a contract The Company capitalizes the costs associated with the devices used in the Company's portfolio of drug-device combination products, which are used in satisfaction of future performance obligations. Capital expenditures for these devices represent cash outflows for the Company's cost to produce the asset, which is classified in property, plant and equipment, net on the consolidated balance sheets and expensed to cost of sales over the useful life of the equipment. Product Royalty Revenues The Company licensed certain rights to Amitiza ® (lubiprostone) ("Amitiza") to third parties in exchange for royalties on net sales of the product. The Company recognized such royalty revenue as the related sales occurred. Contract Balances Accounts receivable are recorded when the right to consideration becomes unconditional. Payments received from customers are typically based upon payment terms of 30 days. The Company does not maintain contract asset balances aside from the accounts receivable balance as presented on the consolidated balance sheets as costs to obtain a contract are expensed when incurred as the amortization period would have been less than one year. These costs are recorded within SG&A on the consolidated statements of operations. Contract liabilities are recorded when cash payments are received in advance of the Company's performance, including amounts that are refundable. Taxes collected from customers relating to product sales and remitted to governmental authorities are accounted for on a net basis. Accordingly, such taxes are excluded from both net sales and expenses.
Research and Development	Research and Development Internal research and development costs are expensed as incurred. Research and development ("R&D") expenses include salary and benefits, allocated overhead and occupancy costs, clinical trial and related clinical manufacturing costs, contract services, medical affairs and other costs.
Currency Translation	Currency Translation For the Company's non-U.S. subsidiaries that transact in a functional currency other than U.S. dollars, assets and liabilities are translated into U.S. dollars using fiscal year-end exchange rates. Revenues and expenses are translated at the average exchange rates in effect during the related month. The net effect of these translation adjustments is shown in the consolidated financial statements as a component of accumulated other comprehensive income (loss). From time to time, the Company has entered into derivative instruments to mitigate the exposure of movements in certain of these foreign currency transactions. Gains and losses resulting from foreign currency transactions are included in net loss.
Cash and Cash Equivalents	Cash and Cash Equivalents The Company classifies cash on hand and deposits in banks, including commercial paper, money market accounts and other investments it may hold from time to time, with an original maturity to the Company of three months or less, as cash and cash equivalents.
Accounts Receivable and Allowance for Doubtful Accounts	Accounts Receivable and Allowance for Doubtful Accounts
Inventories	Inventories Inventories are recorded at the lower of cost or net realizable value, primarily using the first-in, first-out convention. The Company reduces the carrying value of inventories for those items that are potentially excess, obsolete or slow-moving based on changes in customer demand, technology developments or other economic factors.
Property, Plant and Equipment	Property, Plant and Equipment Property, plant and equipment is stated at cost less accumulated depreciation and impairment. Major renewals and improvements are capitalized, while routine maintenance and repairs are expensed as incurred. Depreciation for property, plant and equipment, other than land and construction in process, is generally based upon the following estimated useful lives, using the straight-line method: Buildings 10 to 45 years Leasehold improvements 1 to 20 years Capitalized software 1 to 10 years Machinery and equipment 1 to 20 years The Company capitalizes certain computer software and development costs incurred in connection with developing or obtaining software for internal use. Upon retirement or other disposal of property, plant and equipment, the cost and related amount of accumulated depreciation are eliminated from the asset and accumulated depreciation accounts, respectively. The difference, if any, between the net asset value and the proceeds is included in net loss. The Company assesses the recoverability of assets or asset groups using undiscounted cash flows whenever events or circumstances indicate that the carrying value of an asset or asset group may not be recoverable. If an asset or asset group is found to be impaired, the amount recognized for impairment is equal to the difference between the carrying value of the asset or asset group and its fair value.
Leases	Leases The Company assesses all contracts at inception to determine whether a lease exists. The Company leases office space, manufacturing and warehousing facilities, equipment and vehicles, which are generally operating leases. Leases with an initial term of 12 months or less are not recorded on the consolidated balance sheet; the Company recognizes lease expense for these leases on a straight-line basis over the lease term. The Company has lease agreements with lease and non-lease components, which are accounted for separately. The Company's lease agreements generally do not contain variable lease payments or any material residual value guarantees.
Goodwill and Other Intangible Assets	Intangible Assets Intangible assets acquired in a business combination are recorded at fair value, while intangible assets acquired in other transactions are recorded at cost. Intangible assets with finite useful lives are amortized according to the pattern in which the economic benefit of the asset is used up over their estimated useful lives, as shown below. The estimated useful lives of the Company's intangible assets as of December 29, 2023 (Successor) were the following: Completed technology 1 to 20 years Amortization expense related to completed technology and certain other intangible assets is included in cost of sales. When a triggering event occurs, the Company evaluates potential impairment of finite-lived intangible assets by first comparing undiscounted cash flows associated with the asset, or the asset group they are part of, to its carrying value. If the carrying value is greater than the undiscounted cash flows, the amount of potential impairment is measured by comparing the fair value of the assets, or asset group, with their carrying value. The fair value of the intangible asset, or asset group, is estimated using an income approach. If the fair value is less than the carrying value of the intangible asset, or asset group, the amount recognized for impairment is equal to the difference between the carrying value of the asset and the fair value of the asset. The Company assesses the remaining useful life and the recoverability of finite-lived intangible assets whenever events or circumstances indicate that the carrying value of an asset may not be recoverable. The Company annually tests the indefinite-lived intangible assets for impairment, or whenever events or changes in circumstances indicate that the carrying value may not be recoverable by either a qualitative or income approach. The Company will compare the fair value of the assets with their carrying value and record an impairment when the carrying value exceeds the fair value.
Contingencies	Contingencies The Company is subject to various legal proceedings and claims, including government investigations, environmental matters, product liability matters, patent infringement claims, antitrust matters, securities class action lawsuits, personal injury claims, employment disputes, contractual and other commercial disputes, and all other legal proceedings, all in the ordinary course of business as further discussed in Note 18. The Company records accruals for contingencies when it is probable that a liability has been incurred and the amount can be reasonably estimated. The Company discounts environmental liabilities using a risk-free rate of return when the obligation is fixed or reasonably determinable. The impact of the discount in the consolidated balance sheets was not material in any period presented. Legal fees, other than those pertaining to environmental matters, are expensed as incurred. Insurance recoveries related to potential claims are recognized up to the amount of the recorded liability when coverage is confirmed and the estimated recoveries are probable of payment. Assets and liabilities are not netted for financial statement presentation.
Share-Based Compensation	Share-Based Compensation
Restructuring	Restructuring
Income Taxes	Income Taxes Deferred tax assets and liabilities are recognized for the expected future tax consequences of events that have been reflected in the consolidated financial statements. Deferred tax assets and liabilities are determined based on the differences between the financial reporting and tax bases of assets and liabilities and operating loss carryforwards, using tax rates expected to be in effect for the years in which the differences are expected to reverse. A valuation allowance is provided to reduce net deferred tax assets if, based upon the available evidence, it is more likely than not that some or all of the deferred tax assets will not be realized. The Company determines whether it is more likely than not that a tax position will be sustained upon examination. The tax benefit of any tax position that meets the more-likely-than-not recognition threshold is calculated as the largest amount that is more than 50.0% likely of being realized upon resolution of the uncertainty. To the extent a full benefit is not realized on the uncertain tax position, an income tax liability or a reduction to a deferred tax asset ("contra-DTA(s)") is established. Interest and penalties on income tax obligations, associated with uncertain tax positions, are included in the provision for income taxes. The calculation of the Company's tax liabilities involves dealing with uncertainties in the application of complex tax regulations in a multitude of jurisdictions across the Company's global operations. The Company adjusts these liabilities and contra-DTAs as a result of changing facts and circumstances; however, due to the complexity of some of these uncertainties, the ultimate resolution may result in a payment that is materially different from current estimates of the tax liabilities. If the Company's estimate of tax liabilities proves to be less than the ultimate assessment, an additional charge to expense would result. If payment of these amounts ultimately proves to be less than the recorded amounts, the reversal of the liabilities may result in income tax benefits being recognized in the period when it is determined that the liabilities are no longer necessary. Refer to Note 7 for further information regarding the classification of such amounts in the consolidated balance sheets.
Derivatives, Policy	Derivatives and hedging The Company evaluated the terms and features of its First-Out Takeback Term Loans, Second-Out Takeback Term Loans and Takeback Notes and identified an embedded feature that, in certain scenarios, could materially modify the cash flows of the respective debt instruments. The Company evaluated the embedded feature and determined that it was not clearly and closely related to the underlying debt instruments and did not qualify for any scope exceptions set forth in the accounting standards. Accordingly, this embedded feature is required to be bifurcated from its host instruments and accounted for separately as an embedded derivative liability. As a result, the Company recorded the fair value of the embedded derivatives as of the issuance date as a liability on its consolidated balance sheet. The embedded derivative will be adjusted to fair value each reported period with changes in fair value subsequent to the issuance date recognized within other income (expense) in the consolidated statements of operations. The fair value of the embedded derivative is reflected within current liabilities in the consolidated balance sheet as of December 29, 2023. The fair value of the derivative is determined using the with-and-without model which compares the estimated fair value of the underlying debt instruments with the embedded feature to the estimated fair value of the underlying debt instruments without the embedded feature, with the difference representing the estimated fair value of the embedded derivative feature. The with-and-without model includes significant unobservable estimates, including an estimation of the Company’s probability of an asset sale. Management estimates the probability of the asset sale based on its assessment of entity specific factors and the status of on-going transaction negotiations, if any. Changes in the inputs into the valuation model may have a significant impact on the estimated fair value of the embedded derivatives. For further details, refer to Note 19.

Earnings (Loss) per Share (Poli

Earnings (Loss) per Share (Policies)	12 Months Ended
	Dec. 29, 2023
Earnings (Loss) per Share [Abstract]
Earnings (Loss) Per Share Policy	Loss per share is computed by dividing net loss by the number of weighted-average shares outstanding during the period. Dilutive securities, including participating securities, have not been included in the computation of loss per share as the Company reported a net loss from continuing operations during all periods presented below and therefore, the impact would have been anti-dilutive.

Reorganizations (Tables)

Reorganizations (Tables)	12 Months Ended
	Dec. 29, 2023
Reorganizations [Abstract]
Schedule of Interest Expense Incurred and Paid	Interest expense incurred and paid with respect to the incremental adequate protection payments of 200 basis points and 250 basis points on the Predecessor Revolver and the Predecessor Term Loans, respectively, were as follows: Predecessor Period from Year Ended December 31, 2021 Interest expense incurred for adequate protection payments $ 28.8 $ 63.1 Cash paid for adequate protection payments 28.8 66.7

Fresh-Start Accounting (Tables)

Fresh-Start Accounting (Tables)			12 Months Ended
	Nov. 14, 2023	Jun. 16, 2022	Dec. 29, 2023
Reorganizations [Abstract]
Enterprise Value Reconciliation	The following table reconciles the enterprise value to the implied fair value of the Successor's equity as of the 2023 Effective Date: Enterprise value $ 2,950.0 Plus: Non-operating assets, net (1) 290.0 Less: Fair value of debt (1,882.7) Less: Fair value of Acthar Gel-Related Settlement and Terlivaz contingent value rights (162.5) Successor equity value $ 1,194.8 (1) Represents non-operating assets and liabilities which were excluded from the enterprise value as put forth in the disclosure statement as there were no cash projections associated with these net assets. Upon the application of fresh-start accounting, the Company allocated the reorganization value to its individual assets based on their estimated fair values. Reorganization value represents the fair value of the Successor’s assets before considering liabilities. The following table reconciles the Company's enterprise value to its reorganization value as of the 2023 Effective Date: Enterprise value $ 2,950.0 Plus: Non-operating assets, net 290.0 Plus: Current liabilities (excluding debt or debt-like items) (1) 404.8 Plus: Other non-current liabilities (excluding debt or debt-like items) (2) 172.1 Reorganization value of Successor assets $ 3,816.9	The following table reconciles the enterprise value to the implied fair value of the Company's equity as of the 2020 Effective Date: Enterprise value $ 5,223.0 Plus: Enterprise value adjustments (1) 197.0 Adjusted enterprise value 5,420.0 Plus : Cash and cash equivalents 297.9 Plus: Non-operating assets, net (2) 178.7 Less: Fair value of debt (3,067.2) Less: Fair value of Opioid-Related Litigation Settlement, Acthar Gel-Related Settlement, StrataGraft PRV proceeds and Terlivaz contingent value rights (625.8) Equity value $ 2,203.6 (1) Represents incremental tax benefits not contemplated in the projections utilized in the disclosure statement. (2) Represents non-operating assets and liabilities which were excluded from the enterprise value as put forth in the disclosure statement as there were no cash projections associated with these net assets. Upon the application of fresh-start accounting, the Company allocated the reorganization value to its individual assets based on their estimated fair values. Reorganization value represents the fair value of the Company’s assets before considering liabilities. The following table reconciles the Company's enterprise value to its reorganization value as of the 2020 Effective Date: Adjusted enterprise value $ 5,420.0 Plus : Cash and cash equivalents 297.9 Plus: Non-operating assets, net 178.7 Plus: Current liabilities (excluding debt or debt-like items) 522.5 Plus: Other non-current liabilities (excluding debt or debt-like items) 183.2 Reorganization value of assets $ 6,602.3
Fresh-Start Four Column Balance Sheet	The four-column consolidated balance sheet as of November 14, 2023 is as follows: Predecessor Reorganization Adjustments Fresh-Start Adjustments Successor Assets Current Assets: Cash and cash equivalents $ 314.1 $ (127.3) (a) $ — $ 186.8 Accounts receivable, less allowance for doubtful accounts 467.7 — — 467.7 Inventories 778.7 — 257.6 (o) 1,036.3 Prepaid expenses and other current assets 149.3 6.4 (b) (0.7) (p) 155.0 Total current assets 1,709.8 (120.9) 256.9 1,845.8 Property, plant and equipment, net 468.6 — (150.2) (q) 318.4 Intangible assets, net 2,258.3 — (1,633.7) (r) 624.6 Deferred income taxes — 586.6 (c) 208.5 (s) 795.1 Other assets 222.9 (2.4) (d) 12.5 (t) 233.0 Total Assets $ 4,659.6 $ 463.3 $ (1,306.0) $ 3,816.9 Liabilities and Shareholders' Equity Current Liabilities: Current maturities of long-term debt $ 378.7 $ (370.0) (e) $ — $ 8.7 Accounts payable 93.2 (19.4) (f) — 73.8 Accrued payroll and payroll-related costs 81.6 — — 81.6 Accrued interest 32.2 (31.5) (g) — 0.7 Income taxes payable 2.7 — — 2.7 Accrued and other current liabilities 222.1 31.6 (h) (0.1) (u) 253.6 Acthar Gel-Related Settlement — 21.4 (i) — 21.4 Total current liabilities 810.5 (367.9) (0.1) 442.5 Long-term debt — 1,858.9 (e) — 1,858.9 Pension and postretirement benefits 39.4 — — 39.4 Environmental liabilities 34.6 — — 34.6 Deferred income taxes 1.3 — (1.3) (v) — Other income tax liabilities 19.6 — — 19.6 Other liabilities 65.9 7.5 (j) 27.6 (w) 101.0 Acthar Gel-Related Settlement — 214.7 (i) (88.6) (x) 126.1 Liabilities subject to compromise 4,932.1 (4,932.1) (k) — — Total Liabilities 5,903.4 (3,218.9) (62.4) 2,622.1 Shareholders' Equity: Predecessor ordinary shares 0.1 (0.1) (l) — — Successor ordinary shares — 0.2 (l) — 0.2 Predecessor ordinary shares held in treasury (0.1) 0.1 (l) — — Predecessor additional paid-in capital 2,199.9 (2,199.9) (l) — — Successor additional paid-in capital — 1,194.6 (l) — 1,194.6 Predecessor accumulated other comprehensive income 10.4 0.7 (m) (11.1) (y) — Retained (deficit) earnings (3,454.1) 4,686.6 (n) (1,232.5) (z) — Total Shareholders' Equity (1,243.8) 3,682.2 (1,243.6) 1,194.8 Total Liabilities and Shareholders' Equity $ 4,659.6 $ 463.3 $ (1,306.0) $ 3,816.9	The four-column consolidated balance sheet as of June 16, 2022 was as follows: Predecessor Reorganization Adjustments Fresh-Start Adjustments Successor (1) Assets Current Assets: Cash and cash equivalents $ 1,392.6 $ (1,094.7) (a) $ — $ 297.9 Accounts receivable, less allowance for doubtful accounts 387.4 — — 387.4 Inventories 375.2 — 851.8 (q) 1,227.0 Prepaid expenses and other current assets 322.6 75.3 (b) (58.3) (r) 339.6 Current asset held for sale — — 100.0 (j) 100.0 Total current assets 2,477.8 (1,019.4) 893.5 2,351.9 Property, plant and equipment, net 748.6 — (299.2) (s) 449.4 Intangible assets, net 5,166.6 — (2,014.4) (t) 3,152.2 Deferred income taxes — — 453.4 (l) 453.4 Other assets 222.8 (3.9) (c) (23.5) (u) 195.4 Total Assets $ 8,615.8 $ (1,023.3) $ (990.2) $ 6,602.3 Liabilities and Shareholders' Equity Current Liabilities: Current maturities of long-term debt $ 1,389.9 $ (1,355.2) (d) $ — $ 34.7 Accounts payable 156.4 (53.8) (e) — 102.6 Accrued payroll and payroll-related costs 71.4 — — 71.4 Accrued interest 20.8 (13.0) (f) — 7.8 Acthar Gel-Related Settlement — 16.5 (g) — 16.5 Opioid-Related Litigation Settlement — 200.0 (h) — 200.0 Accrued and other current liabilities 296.1 50.8 (i) (6.1) (v) 340.8 Current liability held for sale — 35.0 (j) — 35.0 Total current liabilities 1,934.6 (1,119.7) (6.1) 808.8 Long-term debt — 3,050.9 (d) (18.4) (w) 3,032.5 Acthar Gel-Related Settlement — 63.2 (g) — 63.2 Opioid-Related Litigation Settlement liability — 304.3 (h) — 304.3 Pension and postretirement benefits 27.6 27.2 (k) — 54.8 Environmental liabilities 37.1 — — 37.1 Deferred income taxes 20.4 102.7 (l) (121.7) (l) 1.4 Other income tax liabilities 75.9 — (61.9) (x) 14.0 Other liabilities 68.6 23.6 (m) (9.6) (v) 82.6 Liabilities subject to compromise 6,402.7 (6,402.7) (n) — — Total Liabilities 8,566.9 (3,950.5) (217.7) 4,398.7 Shareholders' Equity: Predecessor preferred shares — — — — Predecessor ordinary A shares — — — — Predecessor ordinary shares 18.9 (18.9) (o) — — Successor ordinary shares — 0.1 (o) — 0.1 Predecessor ordinary shares held in treasury (1,616.1) 1,616.1 (o) — — Predecessor additional paid-in capital 5,599.5 (5,599.5) (o) — — Successor additional paid-in capital — 2,203.5 (o) — 2,203.5 Predecessor accumulated other comprehensive loss (9.9) — 9.9 (y) — Retained (deficit) earnings (3,943.5) 4,725.9 (p) (782.4) (z) — Total Shareholders' Equity 48.9 2,927.2 (772.5) 2,203.6 Total Liabilities and Shareholders' Equity $ 8,615.8 $ (1,023.3) $ (990.2) $ 6,602.3 (1) The term Successor was used to illustrate the four column consolidated balance sheet as of the 2020 Effective Date. Upon adoption of fresh-start accounting on the 2023 Effective Date, all balances in this four-column consolidated balance sheet became Predecessor period balances.
Reorganization Adjustments, Cash and Cash Equivalents	The table below reflects the sources and uses of cash on the 2023 Effective Date: Uses: Payment of professional fees $ 19.4 Payment to fund professional fees escrow (prepaid and other current assets restricted cash) 24.0 Payment of costs, fees and expenses related to exit-financing activities and accrued and unpaid interest on certain pre-emergence debt 33.3 Payment of cash sweep 50.6 Total Uses of Cash $ 127.3	The table below reflects the sources and uses of cash on the 2020 Effective Date: Sources: Proceeds from the 2028 First Lien Notes $ 637.0 Total Sources 637.0 Uses: Payment of Predecessor revolving credit facility (900.0) Upfront payment of the Opioid-Related Litigation Settlement (447.4) Upfront payment of the Acthar Gel-Related Settlement, inclusive of settlement interest (17.8) Payment of secured, administrative, priority and trade claims (26.2) Payment of professional fees (43.5) Payment to fund professional fees escrow (prepaid and other current assets restricted cash) (89.0) Payment of general unsecured claims (135.0) Payment of noteholder consent fees (19.3) Payment of costs, fees and expenses related to exit-financing activities, an exit fee associated with predecessor senior secured loans and accrued and unpaid interest on certain pre-emergence debt (53.5) Total Uses (1,731.7) Net Uses of Cash $ (1,094.7)
Adjustment Adjustment, Current Liabilities		The following table reconciles reorganization adjustments to accrued and other current liabilities: Severance - Exiting Chief Executive Officer ("CEO") $ 5.7 Reinstatement of various successor obligations from LSTC 15.4 Success fees for professionals incurred on 2020 Effective Date 29.7 $ 50.8
Reorganization Adjustments, Liabilities Subject to Compromise	LSTC were settled as follows in accordance with the 2023 Plan (in millions) : Liabilities subject to compromise Accrued interest $ 158.8 Debt (1) 3,512.1 Acthar Gel-Related Settlement liability (1) 236.1 Opioid-Related Litigation Settlement liability (1) 1,025.0 Other non-current liabilities 0.1 Total liabilities subject to compromise $ 4,932.1 To be reinstated on the 2023 Effective Date: Acthar Gel-Related Settlement liability $ (236.1) Other non-current liabilities (0.1) Total liabilities reinstated $ (236.2) Consideration provided to settle amounts per the 2023 Plan Issuance of Successor ordinary shares $ (1,169.7) Issuance of Opioid CVRs (25.1) Issuance of Second-Out Takeback Term Loans and Second-Out Takeback Notes (1,535.1) Total consideration provided to settle amounts per the 2023 Plan $ (2,729.9) Gain on settlement of liabilities subject to compromise $ 1,966.0	LSTC were settled as follows in accordance with the 2020 Plan (in millions) : Liabilities subject to compromise Accounts payable $ 17.7 Accrued interest 35.2 Debt 3,746.2 Environmental liabilities 67.2 Acthar Gel-Related Settlement liability 630.0 Opioid-Related Litigation Settlement liability 1,722.4 Other current and non-current liabilities 151.6 Pension and postretirement benefits 32.4 Total liabilities subject to compromise $ 6,402.7 Reinstated on the 2020 Effective Date: Accounts payable $ (0.1) Other current and non-current liabilities (27.3) Pension and postretirement benefits (32.4) Total liabilities reinstated $ (59.8) Consideration provided to settle amounts per the 2020 Plan Issuance of successor common stock $ (2,189.7) Issuance of Opioid Warrants (13.9) Issuance of First Lien Term Loans and 2025 Second Lien Notes (1,778.3) Acthar Gel-Related Settlement liability (79.7) Opioid-Related Litigation Settlement liability (504.3) Issuance of 2029 Second Lien Notes to holders of the Guaranteed Unsecured Notes (190.2) Contingent liabilities for proceeds of sale of StrataGraft PRV and Terlivaz CVR (41.8) Cash payment (601.3) Total consideration provided to settle amounts per the 2020 Plan $ (5,399.2) Gain on settlement of liabilities subject to compromise $ 943.7
Reorganization Adjustment, Equity	Pursuant to the 2023 Plan, as of the 2023 Effective Date, all Predecessor preferred and ordinary shares were cancelled without any distribution. The following table reconciles reorganization adjustments made to Successor ordinary shares, Opioid CVRs and additional paid in capital: Par value of 19,696,335 shares of Successor ordinary shares issued to holders of the Predecessor First Lien Notes and Second Lien Notes (par valued at $0.01 per share) $ 0.2 Fair value of Opioid CVRs issued to the Trust (1) 25.1 Additional paid in capital - Successor ordinary shares 1,169.5 Successor equity $ 1,194.8 (1) The fair value of the Opioid CVRs were estimated using a Black-Scholes model with the following assumptions: $60.28 implied share price of the Successor; exercise price per share of $99.36; expected volatility of 65.0%; risk free interest rate of 4.49%, continuously compounded; and a holding period of four years. The expected volatility assumption is based on the historical and implied volatility of the Company's peer group with similar business models.	Pursuant to the 2020 Plan, as of the 2020 Effective Date, all of the Company's preferred and ordinary shares in existence prior to the 2020 Effective Date were cancelled without any distribution. The following table reconciles reorganization adjustments made to the Company's common stock, Opioid Warrants and additional paid in capital: Par value of 13,170,932 shares of Common Stock issued to former holders of the Guaranteed Unsecured Notes (par valued at $0.01 dollars per share) $ 0.1 Fair value of Opioid Warrants issued to holders of the Guaranteed Unsecured Notes (1) 13.9 Additional paid in capital - Common Stock 2,189.6 Equity $ 2,203.6 (1) The fair value of the Opioid Warrants was estimated using a Black-Scholes model with the following assumptions: $18.50 stock price of the Company; exercise price per share of $103.40; expected volatility of 62.28%; risk free interest rate of 3.34%, continuously compounded; and a holding period of six years. The expected volatility assumption is based on the historical and implied volatility of the Company's peer group with similar business models.
Reorganization, Retained Deficit	Retained (deficit) earnings - The cumulative effect of the consummation of the 2023 Plan on the Predecessor's retained deficit is as follows: Gain on settlement of LSTC $ 1,966.0 Professional and exit fees (24.0) Release of prepaid insurance (1) and directors fees (20.0) Fair value of First-Out Takeback Term Loans and related embedded derivative (21.2) Income tax benefit on plan adjustments 585.9 Cancellation of Predecessor equity 2,199.9 Net impact on retained earnings $ 4,686.6 (1) Write off of prepaid expenses related to premiums for the Predecessor's directors' and officers' insurance policy.	Retained deficit - The cumulative effect of the consummation of the 2020 Plan on the Company's retained deficit was as follows: Gain on settlement of LSTC $ 943.7 Professional, success and exit fees (91.6) Release of prepaid success fee (10.9) Release of prepaid insurance (1) (9.2) Accrual of severance for former CEO (5.7) Income tax expense on plan adjustments (102.7) Cancellation of predecessor equity 4,002.3 Net impact on retained deficit $ 4,725.9 (1) Write off of prepaid expenses related to premiums for the predecessor's directors' and officers' insurance policy in existence prior to the 2020 Effective Date.
Fresh-Start Adjustments, Retained Deficit	The cumulative effect of the fresh-start accounting on the Successor's retained deficit is as follows: Fresh-start adjustment: Inventories $ 257.6 Property, plant and equipment (150.2) Intangible assets (1,633.7) Acthar Gel-Related Settlement 88.6 Other assets and liabilities (15.0) Total fresh-start adjustments impacting reorganization items, net (1,452.7) Fresh-start adjustments to accumulated other comprehensive income, net of zero tax benefit 11.1 Total fresh-start adjustments recorded to income tax benefit 209.1 Net fresh-start impact to accumulated deficit $ (1,232.5)	The cumulative effect of the fresh-start accounting on the predecessor's retained deficit as of the 2020 Effective Date was as follows: Fresh-start adjustment: Inventories $ 851.8 Property, plant and equipment, net (299.2) Intangible assets, net (2,014.4) Current asset held for sale 100.0 Debt 18.4 Other assets and liabilities (11.2) Total fresh-start adjustments impacting reorganization items, net (1,354.6) Fresh-start adjustments to accumulated other comprehensive income, net of $0.3 million of tax benefit (9.9) Total fresh-start adjustments recorded to income tax benefit 582.1 Net fresh-start impact to accumulated deficit $ (782.4)
Reorganization Adjustments, Debt	Reflects the fair value adjustments to the carrying value of debt instruments impacted by the 2023 Plan as determined by the Black-Derman-Toy model as follows: First-Out Takeback Term Loans $ 15.0 Second-Out Takeback Term Loans 46.3 Takeback Notes 59.3 Total fair value adjustment to debt instruments $ 120.6	Fair value adjustments to the carrying value of debt instruments impacted by the 2020 Plan as determined by the Black-Derman-Toy model as follows: 2017 Replacement Term Loans $ (169.4) 2018 Replacement Term Loans (42.2) 2025 Second Lien Notes (95.7) 2029 Second Lien Notes (184.8) Total fair value adjustment to debt instruments $ (492.1)
Schedule of Debtor Reorganization Items, net			Reorganization items, net, were comprised of the following: Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 Gain on settlements of LSTC $ — $ (1,966.0) $ — $ (943.7) $ — Loss on fresh-start adjustments — 1,452.7 — 1,354.6 — Adjustments of other claims — 1,139.5 — 5.4 (0.5) Professional and other service provider fees 4.0 61.7 23.2 161.1 405.6 Success fees for professional service providers — — — 44.3 — Debt financing — 154.6 — — — Debt valuation adjustments — 21.2 — — 23.1 Write off of prepaid premium for directors and officers' insurance policies, net, and directors fees — 20.0 — 9.2 — Acceleration of the vesting of Predecessor equity awards upon the 2023 Effective Date — 9.0 — — — Total reorganization items, net $ 4.0 $ 892.7 $ 23.2 $ 630.9 $ 428.2

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 29, 2023
Accounting Policies [Abstract]
Schedule of Useful Lives for Property, Plant and Equipment	Property, Plant and Equipment Property, plant and equipment is stated at cost less accumulated depreciation and impairment. Major renewals and improvements are capitalized, while routine maintenance and repairs are expensed as incurred. Depreciation for property, plant and equipment, other than land and construction in process, is generally based upon the following estimated useful lives, using the straight-line method: Buildings 10 to 45 years Leasehold improvements 1 to 20 years Capitalized software 1 to 10 years Machinery and equipment 1 to 20 years The Company capitalizes certain computer software and development costs incurred in connection with developing or obtaining software for internal use. Upon retirement or other disposal of property, plant and equipment, the cost and related amount of accumulated depreciation are eliminated from the asset and accumulated depreciation accounts, respectively. The difference, if any, between the net asset value and the proceeds is included in net loss. The Company assesses the recoverability of assets or asset groups using undiscounted cash flows whenever events or circumstances indicate that the carrying value of an asset or asset group may not be recoverable. If an asset or asset group is found to be impaired, the amount recognized for impairment is equal to the difference between the carrying value of the asset or asset group and its fair value.
Schedule of Useful Lives for Finite Lived Intangible Assets	The estimated useful lives of the Company's intangible assets as of December 29, 2023 (Successor) were the following: Completed technology 1 to 20 years
Shipping and Handling Cost	Shipping costs included in SG&A expenses in continuing operations were as follows: Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 Shipping costs $ 3.5 $ 22.3 $ 13.9 $ 12.8 $ 23.6

Revenue from Contracts with C_2

Revenue from Contracts with Customers (Tables)	12 Months Ended
	Dec. 29, 2023
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue	Product sales transferred to customers at a point in time and over time were as follows: Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 Product sales transferred at a point in time 85.3 % 83.2 % 83.0 % 80.8 % 79.4 % Product sales transferred over time 14.7 16.8 17.0 19.2 20.6
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction	Transaction price allocated to the remaining performance obligations The following table includes estimated revenue from contracts extending greater than one year for certain of the Company's hospital products that are expected to be recognized in the future related to performance obligations that were unsatisfied or partially unsatisfied as of December 29, 2023 (Successor): Fiscal 2024 (1) $ 41.6 Fiscal 2025 (1) 23.7 Thereafter 4.2
Disaggregation of Revenue - Royalty	The associated royalty revenue recognized was as follows: Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 Royalty revenue $ 0.1 $ 4.3 $ 36.2 $ 34.9 $ 102.4
Sales Reserve Rollforward	The following table reflects activity in the Company's sales reserve accounts: Rebates and Chargebacks (1) Product Returns Other Sales Deductions Total Balance as of December 25, 2020 (Predecessor) 196.5 26.6 12.3 235.4 Provisions 2,087.1 23.7 55.2 2,166.0 Payments or credits (2,041.8) (28.8) (58.0) (2,128.6) Balance as of December 31, 2021 (Predecessor) 241.8 21.5 9.5 272.8 Provisions 693.4 5.2 17.1 715.7 Payments or credits (684.6) (8.1) (18.9) (711.6) Balance as of June 16, 2022 (Predecessor) $ 250.6 $ 18.6 $ 7.7 $ 276.9 Balance as of June 17, 2022 (Predecessor) $ 250.6 $ 18.6 $ 7.7 $ 276.9 Provisions 804.4 7.0 36.7 848.1 Payments or credits (789.7) (9.6) (31.7) (831.0) Balance as of December 30, 2022 (Predecessor) $ 265.3 $ 16.0 $ 12.7 $ 294.0 Provisions 1,368.8 9.9 43.3 1,422.0 Payments or credits (1,410.1) (13.1) (42.3) (1,465.5) Balance as of November 14, 2023 (Predecessor) $ 224.0 $ 12.8 $ 13.7 $ 250.5 Balance as of November 15, 2023 (Successor) $ 224.0 $ 12.8 $ 13.7 $ 250.5 Provisions 173.0 3.0 6.9 182.9 Payments or credits (195.4) (1.3) (9.3) (206.0) Balance as of December 29, 2023 (Successor) $ 201.6 $ 14.5 $ 11.3 $ 227.4 (1) Includes $59.0 million and $89.3 million of accrued Medicaid and $35.1 million and $55.3 million of accrued rebates as of December 29, 2023 (Successor) and December 30, 2022 (Predecessor), respectively, included within accrued and other current liabilities in the consolidated balance sheets.

Restructuring and Related Cha_2

Restructuring and Related Charges (Tables)	12 Months Ended
	Dec. 29, 2023
Restructuring and Related Activities [Abstract]
Schedule of Restructuring and Related Charges by Segment	Net restructuring and related charges by segment were as follows: Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 Specialty Brands $ — $ — $ — $ — $ 0.1 Specialty Generics — — 0.8 3.5 4.9 Corporate — 1.7 11.3 6.1 24.0 Restructuring and related charges, net — 1.7 12.1 9.6 29.0 Less: accelerated depreciation — (0.8) (1.0) — (2.1) Restructuring charges, net $ — $ 0.9 $ 11.1 $ 9.6 $ 26.9
Schedule of Net Restructuring and Related Charges	Net restructuring and related charges by program from continuing operations were comprised of the following: Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 2018 Program $ — $ 1.7 $ 12.1 $ 9.6 $ 29.0 Less: non-cash charges, including accelerated depreciation — (0.8) (2.2) (3.6) (6.3) Total charges expected to be settled in cash $ — $ 0.9 $ 9.9 $ 6.0 $ 22.7
Schedule of Restructuring Reserves by Type of Cost	The following table summarizes cash activity for restructuring reserves, substantially all of which related to contract termination costs, employee severance and benefits and exiting of certain facilities: 2018 Program Balance as of December 25, 2020 (Predecessor) $ 1.0 Charges from continuing operations 23.7 Changes in estimate from continuing operations (1.0) Cash payments (12.8) Balance as of December 31, 2021 (Predecessor) 10.9 Charges from continuing operations 7.1 Changes in estimate from continuing operations (1.1) Cash payments (15.9) Balance as of June 16, 2022 (Predecessor) $ 1.0 Balance as of June 17, 2022 (Predecessor) $ 1.0 Charges from continuing operations 12.7 Changes in estimate from continuing operations (2.8) Cash payments (6.3) Balance as of December 30, 2022 (Predecessor) 4.6 Charges from continuing operations 1.3 Changes in estimate from continuing operations (0.4) Cash payments (5.4) Balance as of November 14, 2023 (Predecessor) $ 0.1 Balance as of November 15, 2023 (Successor) and December 29, 2023 (Successor) $ 0.1
Schedule of Restructuring Charges Incurred Cumulative to Date	As of December 29, 2023 (Successor), net restructuring and related charges incurred cumulative to date for the 2018 Program were as follows: Specialty Brands $ 3.1 Specialty Generics 19.3 Corporate 96.9 $ 119.3

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 29, 2023
Income Tax Disclosure [Abstract]
Schedule of Components of Income from Continuing Operations before Income Taxes	The domestic and international components (1) of loss from continuing operations before income taxes were as follows: Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 Domestic $ (46.1) $ (3,628.8) $ (359.4) $ (2,883.3) $ (512.2) International (0.1) 1,719.7 (290.9) 2,072.0 (317.6) Total $ (46.2) $ (1,909.1) $ (650.3) $ (811.3) $ (829.8) (1) Domestic reflects Ireland.
Schedule of Significant Components of Income Taxes Related to Continuing Operations	Significant components (1) of income taxes related to continuing operations were as follows: Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 Current: Domestic $ (0.8) $ 36.6 $ (32.8) $ 33.7 $ (33.7) International (0.6) 4.7 5.7 (57.6) (12.7) Current income tax (benefit) provision (1.4) 41.3 (27.1) (23.9) (46.4) Deferred: Domestic (6.1) (300.6) (44.6) (82.3) (59.5) International (0.5) (18.5) 19.7 (391.1) (0.4) Deferred income tax (benefit) provision (6.6) (319.1) (24.9) (473.4) (59.9) Total $ (8.0) $ (277.8) $ (52.0) $ (497.3) $ (106.3) (1) Domestic reflects Ireland.
Schedule of Reconciliation of Income Taxes at Statutory Rate and Tax Provision	The reconciliation between domestic income taxes at the statutory rate and the Company's provision for income taxes on continuing operations is as follows: Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 Benefit for income taxes at domestic statutory income tax rate (1) $ (5.8) $ (238.6) $ (81.3) $ (101.4) $ (103.7) Adjustments to reconcile to income tax provision: Rate difference between domestic and international jurisdictions (2.2) 56.6 (4.7) 226.5 (224.9) Adjustments to accrued income tax liabilities and uncertain tax positions (2) — — — — (9.7) Credits, principally research and orphan drug — (1.9) — (0.9) (4.7) Permanently nondeductible and nontaxable items (3) (0.2) 3.2 3.1 (1.7) 9.8 Emergence — (103.7) — (31.6) — Withholding tax on Swiss distribution — — 4.7 — — Legal entity reorganization (4) — (44.7) — — — Reorganization items, net — 6.7 1.7 15.7 36.9 Other 0.1 0.6 (1.4) (3.1) 0.3 Valuation allowances (5) 0.1 44.0 25.9 (600.8) 189.7 (Benefit) provision for income taxes $ (8.0) $ (277.8) $ (52.0) $ (497.3) $ (106.3) (1) The statutory tax rate reflects the Irish statutory tax rate of 12.5%. (2) Includes interest and penalties on accrued income tax liabilities and uncertain tax positions. (3) For fiscal 2021 (Predecessor), the permanently nondeductible and nontaxable items were primarily driven by the Opioid-Related Litigation Settlement loss. (4) Associated unrecognized tax expense is netted within this line. (5) The period from January 1, 2022 through June 16, 2022 (Predecessor) consists of $512.1 million of tax benefit for the reduction in the valuation allowance on the Company's deferred tax assets due to the alleviation of the previous substantial doubt about the Company's ability to continue as a going concern.
Schedule of Unrecognized Tax Benefit Activity	The following table summarizes the activity related to the Company's unrecognized tax benefits, excluding interest: Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 Balance at beginning of period $ 33.3 $ 24.8 $ 24.8 $ 333.5 $ 349.0 Additions related to current year tax positions — 8.5 — — — Additions related to prior period tax positions — — — — 9.3 Reductions related to prior period tax positions — — — (306.1) (2.8) Settlements — — — (2.6) (0.2) Lapse of statutes of limitations — — — — (21.8) Balance at end of period $ 33.3 $ 33.3 $ 24.8 $ 24.8 $ 333.5
Schedule of Unrecongized Tax Benefits Balance Sheet Location	Unrecognized tax benefits, excluding interest, were reported in the following consolidated balance sheet captions in the amounts shown: Successor Predecessor December 29, 2023 December 30, 2022 Deferred income tax asset 17.9 9.4 Other income tax liabilities 15.4 15.4 $ 33.3 $ 24.8
Schedule of Income Taxes Payable	Income taxes payable, including uncertain tax positions and related interest accruals, was reported in the following consolidated balance sheet captions in the amounts shown: Successor Predecessor December 29, 2023 December 30, 2022 Accrued and other current liabilities $ 1.7 $ 3.6 Other income tax liabilities 19.6 18.2 $ 21.3 $ 21.8
Schedule of Income Tax Receivables and Other Assets	Tax receivables were included in the following consolidated balance sheet captions in the amounts shown: Successor Predecessor December 29, 2023 December 30, 2022 Prepaid expenses and other current assets 11.5 179.5
Schedule of Deferred Taxes Activity	The components of the net deferred tax asset (liability) at the end of each fiscal year were as follows: Successor Predecessor December 29, 2023 December 30, 2022 Deferred tax assets: Tax loss and credit carryforward $ 3,600.7 $ 3,646.0 Capital tax loss carryforward and related assets 983.5 1,412.6 Intangible assets 571.5 278.4 Opioid-Related Litigation Settlement liability — 111.7 Excess interest 95.1 84.0 Other 231.3 159.8 5,482.1 5,692.5 Deferred tax liabilities: Investment in partnership (68.7) (67.4) Other (28.6) (157.0) (97.3) (224.4) Net deferred tax asset before valuation allowances 5,384.8 5,468.1 Valuation allowances (4,583.8) (4,992.9) Net deferred tax asset (liability) $ 801.0 $ 475.2
Schedule of Deferred Tax Assets and Liabilities on Balance Sheet	Deferred taxes were included in the following consolidated balance sheet captions in the amounts shown: Successor Predecessor December 29, 2023 December 30, 2022 Deferred income tax asset $ 801.0 $ 475.5 Deferred income tax liability — (0.3) Net deferred tax asset (liability) $ 801.0 $ 475.2

Earnings (Loss) per Share (Tabl

Earnings (Loss) per Share (Tables)	12 Months Ended
	Dec. 29, 2023
Earnings (Loss) per Share [Abstract]
Schedule of Earnings (Loss) per Share	The weighted-average number of shares outstanding used in the computations of both basic and diluted loss per share were as follows ( in millions ): Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 Basic 19.7 13.3 13.2 84.8 84.7

Inventories (Tables)

Inventories (Tables)	12 Months Ended
	Dec. 29, 2023
Inventory, Net [Abstract]
Schedule of Inventories	Inventories were comprised of the following at the end of each period: Successor Predecessor December 29, December 30, Raw materials $ 98.0 $ 80.2 Work in process 501.8 552.1 Finished goods 382.9 315.3 Inventories $ 982.7 $ 947.6

Property, Plant and Equipment (

Property, Plant and Equipment (Tables)	12 Months Ended
	Dec. 29, 2023
Property, Plant and Equipment [Line Items]
Depreciation of Property, Plant and Equipment	Depreciation expense was as follows: Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 Depreciation expense $ 9.6 $ 40.7 $ 28.8 $ 40.0 $ 94.7
Schedule of Property, Plant and Equipment	The gross carrying amount and accumulated depreciation of property, plant and equipment were comprised of the following at the end of each period: Successor Predecessor December 29, 2023 December 30, 2022 Land $ 37.7 $ 51.0 Buildings 94.6 127.2 Capitalized software 1.9 17.5 Machinery and equipment 136.3 216.8 Construction in process 60.8 72.5 331.3 485.0 Less: accumulated depreciation (9.6) (27.4) Property, plant and equipment, net $ 321.7 $ 457.6

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 29, 2023
Leases [Abstract]
Schedule of Lease Assets and Liabilities	Lease assets and liabilities related to the Company's operating leases are reported in the following consolidated balance sheet captions: Successor Predecessor December 29, December 30, Other assets $ 50.9 $ 38.1 Accrued and other current liabilities $ 10.5 $ 10.3 Other liabilities 44.8 30.4 Total lease liabilities $ 55.3 $ 40.7
Lease, Cost	Dependent on the nature of the leased asset, lease expense is included within cost of sales or SG&A. The primary components of lease expense were as follows: Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 Lease cost: Operating lease cost $ 1.8 $ 15.0 $ 7.9 $ 8.7 $ 19.6 Short-term lease cost 0.5 0.9 1.6 0.4 1.1 Variable lease cost — 2.3 1.5 1.2 2.4 Total lease cost $ 2.3 $ 18.2 $ 11.0 $ 10.3 $ 23.1
Lessee, Operating Lease, Liability, Maturity	Contractual maturities of operating lease liabilities as of December 29, 2023 (Successor) were as follows: Fiscal 2024 $ 14.4 Fiscal 2025 13.2 Fiscal 2026 8.9 Fiscal 2027 6.9 Fiscal 2028 6.6 Thereafter 24.7 Total lease payments 74.7 Less: Interest (19.4) Present value of lease liabilities $ 55.3
Lessee, Operating Lease, Lease Terms	Lease terms and discount rates were as follows: Successor Predecessor December 29, December 30, Weighted-average remaining lease term (in years) - operating lease 7.4 6.7 Weighted-average discount rate - operating leases 8.1 % 11.9 %
Lessee, Operating Lease, Cash Flow Information	Other supplemental cash flow information related to leases were as follows: Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 2.4 $ 14.6 $ 9.2 $ 9.4 $ 20.4 Lease assets obtained in exchange for lease obligations: Operating leases — 13.2 7.1 13.4 2.6

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)		12 Months Ended
	Nov. 14, 2023	Dec. 29, 2023
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Intangible Assets		The gross carrying amount and accumulated amortization of intangible assets were comprised of the following at the end of each period: Successor Predecessor December 29, 2023 December 30, 2022 Gross Carrying Amount Accumulated Amortization Gross Carrying Amount Accumulated Amortization Amortizable: Completed technology $ 624.6 $ 16.2 $ 3,041.2 $ 318.7 Non-Amortizable: In-process research and development — 121.3
Finite-lived Intangible Assets Amortization Expense		Intangible asset amortization expense was as follows: Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 Amortization expense $ 16.2 $ 449.6 $ 318.7 $ 281.8 $ 581.1
Schedule of Future Amortization Expense, Intangible Assets		The estimated aggregate amortization expense on intangible assets owned by the Company and being amortized as of December 29, 2023 (Successor) is expected to be as follows: Fiscal 2024 $ 90.3 Fiscal 2025 74.8 Fiscal 2026 68.4 Fiscal 2027 62.0 Fiscal 2028 55.6
Schedule of Intangible Assets and Goodwill	Intangible assets of the Successor as of the 2023 Effective Date consisted of the following: Carrying Amount Amortization Method Amortization Period (in years) Discount Rate Segment Amortizable completed technology: Acthar Gel $ 110.0 Sum of the years digits 10.0 52.3% Specialty Brands Therakos 129.4 Sum of the years digits 9.0 51.5 Specialty Brands Amitiza 12.3 Sum of the years digits 1.0 51.5 Specialty Brands INOmax 41.3 Sum of the years digits 8.0 51.5 Specialty Brands Terlivaz 68.1 Straight-line 5.5 52.5 Specialty Brands Generics 186.7 Straight-line 18.0 14.1 Specialty Generics APAP 76.8 Straight-line 20.0 13.5 Specialty Generics $ 624.6

Debt (Tables)

Debt (Tables)	12 Months Ended
	Dec. 29, 2023
Debt Disclosure [Abstract]
Schedule of Long-term Debt	Debt was comprised of the following at the end of each period: Successor Predecessor December 29, 2023 December 30, 2022 Principal Carrying Value (1) Unamortized Discount and Debt Issuance Costs Principal Carrying Value (2) Unamortized Discount and Debt Issuance Costs First-Out Takeback Term Loan due November 2028 $ 228.8 $ 243.4 $ — $ — $ — $ — Second-Out Takeback Term Loan due November 2028 640.4 685.5 — — — — 14.75% Second-Out Takeback Notes due November 2028 778.6 836.4 — — — — Receivables financing facility due December 2027 — — 2.9 — — — 10.00% first lien senior secured notes due April 2025 — — — 495.0 475.9 — 10.00% second lien senior secured notes due April 2025 — — — 321.9 242.2 — 2017 Replacement Term loan due September 2027 — — — 1,374.1 1,222.1 — 2018 Replacement Term loan due September 2027 — — — 364.8 326.9 — 11.50% first lien senior secured notes due December 2028 — — — 650.0 650.0 20.8 10.00% second lien senior secured notes due June 2029 — — — 328.3 175.5 — Total debt 1,647.8 1,765.3 2.9 3,534.1 3,092.6 20.8 Less: Current portion (6.5) (6.5) — (44.1) (44.1) — Total long-term debt, net of current portion $ 1,641.3 $ 1,758.8 $ 2.9 $ 3,490.0 $ 3,048.5 $ 20.8 (1) Upon adoption of fresh-start accounting upon the emergence from the 2023 Bankruptcy Proceedings, the Company recorded its debt instruments at fair value utilizing the Black-Derman-Toy model, which takes into consideration prepayment options and a credit-adjusted discount rate. Subsequent to the 2023 Effective Date, the Company accounted for its debt instruments utilizing the amortized cost method and amortizes the fair value premium to the principal amount over the term of the respective instruments. Such amortization expense is reflected as interest expense on the consolidated statement of operations for the Successor period. (2) Upon adoption of fresh-start accounting upon the emergence from the 2020 Bankruptcy Proceedings, the Company recorded its debt instruments at fair value utilizing the Black-Derman-Toy model, which takes into consideration prepayment options and a credit-adjusted discount rate. Subsequent to the 2020 Effective Date up through the 2023 Petition Date, the Company accounted for its debt instruments utilizing the amortized cost method and accreted the fair value discount to the principal amount over the term of the respective instruments. Such accretion expense was reflected as interest expense on the consolidated statement of operations for the Predecessor period. As of the petition date of the 2023 Bankruptcy Proceedings, the Company expensed $377.6 million of accelerated accretion to adjust the carrying value up to the principal value or allowed claim amount pursuant to the 2023 Plan and recorded the expense within reorganization items, net in the consolidated statement of operations for the period from December 31, 2022 to November 14, 2023 (Predecessor). Additionally, as a result of the 2023 Bankruptcy Proceedings, the Company expensed $18.5 million of unamortized discount and debt issuance costs, net, recorded in reorganization items, net in the consolidated statement of operations for the period from December 31, 2022 to November 14, 2023 (Predecessor). Refer to Note 3 for further information on reorganization items, net.
Schedule of Applicable Interest Rate on Variable-rate Debt	As of December 29, 2023 (Successor), the applicable interest rate and outstanding principal on the Company's debt instruments were as follows: Applicable interest rate Outstanding principal Fixed-rate instrument 14.8 % $ 778.6 First-Out Takeback Term Loans (1) 11.4 228.8 Second-Out Takeback Term Loans (1) 13.4 640.4
Schedule of Maturities of Long-term Debt	The Company's stated long-term debt principal maturity amounts as of December 29, 2023 are as follows: Fiscal 2024 $ 6.5 Fiscal 2025 8.7 Fiscal 2026 8.7 Fiscal 2027 10.9 Fiscal 2028 1,613.0

Share Plans (Tables)

Share Plans (Tables)	12 Months Ended
	Dec. 29, 2023
Share-Based Payment Arrangement [Abstract]
Schedule of Share Option Activity	Share option activity and information was as follows: Share Options Weighted-Average Exercise Price Outstanding as of December 25, 2020 (Predecessor) 6,069,712 35.95 Expired/Forfeited (516,193) 45.63 Outstanding as of December 31, 2021 (Predecessor) 5,553,519 35.05 Expired/Forfeited (5,553,519) 35.05 Outstanding as of June 16, 2022 (Predecessor) — —
Schedule of Restricted Share Unit Activity	RSU activity was as follows: Shares Weighted-Average Non-vested as of December 25, 2020 (Predecessor) 490,671 20.96 Exercised (186,930) 23.43 Expired/Forfeited (60,844) 19.58 Non-vested as of December 31, 2021 (Predecessor) 242,897 19.40 Expired/Forfeited (242,897) 19.40 Non-vested as of June 16, 2022 (Predecessor) — — Non-vested as of June 17, 2022 (Predecessor) — — Granted 890,485 12.03 Non-vested as of December 30, 2022 (Predecessor) 890,485 12.03 Granted 2,089,814 1.18 Exercised (332,604) 12.89 Expired/Forfeited (2,647,695) 3.35 Non-vested as of November 14, 2023 (Predecessor) — —
Share-based Compensation, Performance Shares Award Outstanding Activity	PSU activity was as follows (1) : Shares Weighted-Average Non-vested as of June 17, 2022 (Predecessor) — — Granted 675,821 8.34 Non-vested as of December 30, 2022 (Predecessor) 675,821 8.34 Granted 1,459,493 10.13 Forfeited (2,135,314) 10.36 Non-vested as of November 14, 2023 (Predecessor) — —
Schedule of Share-based Payment Award, Performance Share Awards, Valuation Assumptions	The assumptions used in the Monte Carlo model for PSUs granted during the period December 31, 2022 through November 14, 2023 (Predecessor) and the period from June 17, 2022 through December 30, 2022 (Predecessor) were as follows: Period from Period from Expected stock price volatility 40.1 % 38.9 % Peer group stock price volatility 124.7 128.0 Correlation of returns 23.8 24.4

Financial Instruments and Fai_2

Financial Instruments and Fair Value Measurements (Tables)	12 Months Ended
	Dec. 29, 2023
Fair Value Disclosures [Abstract]
Schedule of Fair Value of Assets and Liabilities Measured on a Recurring Basis	The following tables provide a summary of the significant assets and liabilities that are measured at fair value on a recurring basis at the end of each period: December 29, 2023 (Successor) Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs Assets: Debt and equity securities held in rabbi trusts $ 43.3 $ 29.1 $ 14.2 $ — Equity securities 28.9 28.9 — — Interest rate cap 12.9 — — 12.9 $ 85.1 $ 58.0 $ 14.2 $ 12.9 Liabilities: Debt derivative liabilities $ 15.1 $ — $ — $ 15.1 Deferred compensation liabilities 21.0 — 21.0 — Contingent consideration liabilities 14.7 — — 14.7 $ 50.8 $ — $ 21.0 $ 29.8 December 30, 2022 (Predecessor) Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs Assets: Debt and equity securities held in rabbi trusts $ 36.6 $ 24.8 $ 11.8 $ — Equity securities 25.5 25.5 — — $ 62.1 $ 50.3 $ 11.8 $ — Liabilities: Deferred compensation liabilities $ 26.0 $ — $ 26.0 $ — Contingent consideration liabilities 7.3 — — 7.3 $ 33.3 $ — $ 26.0 $ 7.3
Schedule of Reconciliation of Changes in Fair Value of Contingent Consideration	The following table summarizes activity for contingent consideration: Balance as of December 30, 2022 (Predecessor) $ 7.3 Fair value adjustments (7.2) Fresh-start adjustment 14.9 Balance as of November 14, 2023 (Predecessor) $ 15.0 Balance as of November 15, 2023 (Successor) $ 15.0 Fair value adjustments (0.3) Balance as of December 29, 2023 (Successor) $ 14.7
Schedule of Carrying Amount and Fair Value of Long-term Debt	Successor Predecessor December 29, 2023 December 30, 2022 Carrying Fair Carrying Fair Level 1: 14.75% Second-Out Takeback Notes due November 2028 $ 836.4 $ 844.4 $ — $ — 10.00% first lien senior secured notes due April 2025 — — 475.9 425.9 10.00% second lien senior secured notes due April 2025 — — 242.2 216.8 11.50% first lien senior secured notes due December 2028 — — 650.0 552.6 10.00% second lien senior secured notes due June 2029 — — 175.5 176.7 Level 2: First-Out Takeback Term Loan Due November 2028 243.4 232.8 — — Second-Out Takeback Term Loan Due November 2028 685.5 654.0 — — 2017 Replacement Term loan due September 2027 — — 1,222.1 1,037.8 2018 Replacement Term loan due September 2027 — — 326.9 274.8 Total Debt $ 1,765.3 $ 1,731.2 $ 3,092.6 $ 2,684.6
Schedules of Concentration of Risk	The following table shows net sales attributable to distributors that accounted for 10.0% or more of the Company's total segment net sales: Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 FFF Enterprises, Inc. 23.1 % 22.3 % 26.1 % 11.8 % *% McKesson Corporation 10.8 * * * * AmerisourceBergen Corporation * 10.0 * * * CuraScript, Inc. * * * 15.6 26.1 * Net sales to this distributor were less than 10.0% of total net sales during the respective periods presented above. The following table shows accounts receivable attributable to distributors that accounted for 10.0% or more of the Company's gross accounts receivable at the end of each period: Successor Predecessor December 29, December 30, AmerisourceBergen Corporation 24.2% 23.3% McKesson Corporation 20.0 17.3 FFF Enterprises, Inc. * 16.2 * Accounts receivable attributable to this distributor was less than 10.0% of total gross accounts receivable at the end of the respective period presented above. The following table shows net sales attributable to products that accounted for 10.0% or more of the Company's total segment net sales: Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 Acthar Gel 23.5 % 22.7 % 28.3 % 25.4 % 26.9 % INOmax 14.5 16.5 16.7 19.0 20.3 Therakos 16.1 13.6 12.5 12.5 12.1 APAP 13.4 11.4 10.7 11.0 *
Schedule of Derivative Liabilities at Fair Value	Significant assumptions utilized in the determination of the fair value are as follows: First and Second-Out Takeback Term Loans: Input Scenario 1 Scenario 2 Scenario 3 Remaining term (years) 5 5 5 Maturity Date November 14, 2028 November 14, 2028 November 14, 2028 Coupon Rate 7.50% - 9.50% + SOFR 7.50% - 9.50% + SOFR 7.50% - 9.50% + SOFR Probability of mandatory prepayment event before November 2025 (1) 25.00% 25.00% 6.25% Estimated timing of mandatory prepayment event before November 2025 (1) August 2024 December 2024 August and December 2024 (1) Represents a significant unobservable input Takeback Notes: Input Scenario 1 Scenario 2 Scenario 3 Remaining term (years) 5 5 5 Maturity Date November 14, 2028 November 14, 2028 November 14, 2028 Coupon Rate 14.75% 14.75% 14.75% Probability of mandatory prepayment event before November 2025 (1) 25.00% 25.00% 6.25% Estimated timing of mandatory prepayment event before November 2025 (1) August 2024 December 2024 August and December 2024 (1) Represents a significant unobservable input

Segment and Geographical Data (

Segment and Geographical Data (Tables)	12 Months Ended
	Dec. 29, 2023
Segment Reporting [Abstract]
Schedule of Segment Reporting Information by Business Segment	Selected information by reportable segment was as follows: Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 Net sales: Specialty Brands $ 139.8 $ 949.2 $ 682.4 $ 587.1 $ 1,547.0 Specialty Generics 103.2 673.7 357.3 287.5 661.8 Net sales $ 243.0 $ 1,622.9 $ 1,039.7 $ 874.6 $ 2,208.8 Operating loss: Specialty Brands $ 9.0 $ 209.9 $ 113.8 $ 267.2 $ 812.8 Specialty Generics (1) 5.8 156.2 (3.6) 65.3 107.9 Segment operating income 14.8 366.1 110.2 332.5 920.7 Unallocated amounts: Corporate and unallocated expenses (2) (4.0) (45.8) (39.3) (48.2) (129.6) Depreciation and amortization (25.8) (490.3) (347.5) (321.8) (675.8) Share-based compensation — (8.9) (1.4) (1.7) (10.2) Restructuring charges, net — (0.9) (11.1) (9.6) (26.9) Non-restructuring impairment charges (3) (3.8) (179.9) — — (154.9) Liabilities management and separation costs (4) (1.4) (157.7) (21.2) (9.0) (1.2) Opioid-Related Litigation Settlement loss — — — — (125.0) Bad debt expense - customer bankruptcy — — (6.4) — — Operating loss $ (20.2) $ (517.4) $ (316.7) $ (57.8) $ (202.9) Depreciation and amortization: Specialty Brands $ 15.3 $ 455.3 $ 323.6 $ 288.4 $ 597.7 Specialty Generics 10.5 35.0 23.9 33.4 78.1 $ 25.8 $ 490.3 $ 347.5 $ 321.8 $ 675.8 (1) Includes $30.0 million of fresh-start inventory-related expense during the period from June 17, 2022 through December 30, 2022 (Predecessor) primarily driven by the Company's change in accounting estimate. (2) Includes administration expenses and certain compensation, legal, environmental and other costs not charged to the Company's reportable segments. (3) Includes $135.9 million and $154.9 million of impairment charges on intangible assets during the period December 31, 2022 through November 14, 2023 (Predecessor) and fiscal 2021 (Predecessor), respectively, as further described in Note 12, a $44.0 million Acthar Gel inventory write-down to net realizable value during the period December 31, 2022 through November 14, 2023 (Predecessor), and $3.8 million of impairment charges on StrataGraft long-lived assets during the period November 15, 2023 through December 29, 2023 (Successor). (4) Represents costs primarily related to professional fees incurred by the Company (including where the Company is responsible for the fees of third parties) in connection with its evaluation of its financial situation and related discussions with its stakeholders prior to the commencement of the 2023 Bankruptcy Proceedings, expenses incurred related to the severance of certain former executives of the Predecessor as a result of the 2020 Bankruptcy Proceedings, in addition to professional fees and costs incurred as the Company explores potential sales of non-core assets to enable further deleveraging post-emergence. As of the 2023 Petition Date and 2020 Petition Date, professional fees directly related to the 2023 Bankruptcy Proceedings and 2020 Bankruptcy Proceedings, respectively, that were previously reflected as liabilities management and separation costs were classified on a go-forward basis as reorganization items, net until the 2023 Effective Date and the 2020 Effective Date, respectively.
Schedule of Net Sales from External Customers by Products	Net sales by product family within the Company's reportable segments were as follows: Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 Acthar Gel $ 57.0 $ 368.3 $ 294.1 $ 221.9 $ 593.6 INOmax 35.3 267.9 173.9 165.8 448.5 Therakos 39.1 220.0 130.5 109.6 266.5 Amitiza (1) 5.0 72.0 77.1 81.5 196.9 Terlivaz 2.3 13.3 1.2 — — Other 1.1 7.7 5.6 8.3 41.5 Specialty Brands 139.8 949.2 682.4 587.1 1,547.0 Opioids 31.6 230.7 117.9 88.8 213.2 ADHD 13.5 101.4 28.4 17.5 37.4 Addiction treatment 10.5 55.6 35.0 30.0 68.3 Other 1.6 8.2 6.8 4.9 12.0 Generics 57.2 395.9 188.1 141.2 330.9 Controlled substances 11.6 75.5 47.0 37.6 93.4 APAP 32.5 184.8 111.4 96.5 215.9 Other 1.9 17.5 10.8 12.2 21.6 API 46.0 277.8 169.2 146.3 330.9 Specialty Generics 103.2 673.7 357.3 287.5 661.8 Net Sales $ 243.0 $ 1,622.9 $ 1,039.7 $ 874.6 $ 2,208.8 (1) Amitiza net sales consist of both product and royalty net sales.
Schedule of Net Sales and Long-Lived Assets by Geographical Area	Selected information by geographic area was as follows: Successor Predecessor Period from Period from Period from Period from Year Ended December 31, 2021 Net sales (1) : U.S. $ 212.8 $ 1,448.9 $ 928.3 $ 784.2 $ 1,991.8 Europe, Middle East and Africa 28.8 157.1 100.4 73.6 181.8 Other 1.4 16.9 11.0 16.8 35.2 Net Sales $ 243.0 $ 1,622.9 $ 1,039.7 $ 874.6 $ 2,208.8 (1) Net sales are attributed to regions based on the location of the entity that records the transaction, none of which relate to the country of Ireland. Successor Predecessor December 29, December 30, Long-lived assets (1) : U.S. $ 165.9 $ 287.3 Europe, Middle East and Africa (2) 164.6 178.0 Other 2.8 3.1 $ 333.3 $ 468.4 (1) Long-lived assets are primarily composed of property, plant and equipment, net. (2) Includes long-lived assets located in Ireland of $162.1 million and $174.9 million as of December 29, 2023 (Successor) and December 30, 2022 (Predecessor), respectively.	[1]
[1] Net sales are attributed to regions based on the location of the entity that records the transaction, none of which relate to the country of Ireland.

Background and Basis of Present

Background and Basis of Presentation (Details) - USD ($) $ in Millions	6 Months Ended	11 Months Ended
	Dec. 30, 2022	Nov. 14, 2023	Jun. 16, 2022
Schedule of Basis of Presentation [Line Items]
Change in Estimate, Fresh-Start, Amount recognized	$ 30
Inventory Turns
Schedule of Basis of Presentation [Line Items]
Change in Estimate, Fresh-Start, Amount recognized	$ 19.9	$ 0.6
Change in Estimate, Fresh-Start			$ 20.5
Indemnification receivable
Schedule of Basis of Presentation [Line Items]
Change in Accounting Policy, Fresh-Start			20.3
Asbestos-related liability
Schedule of Basis of Presentation [Line Items]
Change in Accounting Policy, Fresh-Start			$ 22.8

Bankruptcy (Details)

Bankruptcy (Details) - USD ($) $ / shares in Units, $ in Millions				1 Months Ended	6 Months Ended		11 Months Ended	12 Months Ended
	Nov. 14, 2023	Jun. 16, 2022	Oct. 12, 2020	Dec. 29, 2023	Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 31, 2021	Aug. 24, 2023	Aug. 23, 2023	Jun. 16, 2023
Reorganizations [Line Items]
Restructuring Support Agreement, Proposed Long-Term Debt		$ 375				$ 375
Restructuring Support Agreement, Common Stock Share Percentage Reorganized New Company		100%				100%
Cash paid for interest, net				$ 9	$ 164.1	$ 111.5	$ 316.8	$ 243.2
Accrued interest				20.1	29
Interest Protection Payment, Expense						28.8		63.1
Interest Protection Payment, Paid						$ 28.8		66.7
Debt instrument, face amount				1,647.8	3,534.1
Class of Warrant or Right, Outstanding		3,290,675				3,290,675
Opioid-Related Settlement, Warrants Common Stock Share Percentage Reorganized New Company		19.99%				19.99%
Opioid Warrants, Par value		$ 0.01				$ 0.01
Class of Warrant or Right, Exercise Price of Warrants or Rights	$ 99.36	$ 103.40				$ 103.40	$ 99.36
Acthar Gel-Related Settlement, Term		7 years				7 years
Acthar Gel-Related Settlement, Upfront Payment		$ 15				$ 15
Acthar Gel-Related Settlement, Payment Year One		15				15
Acthar Gel-Related Settlement, Payment Year Two and Three		20				20
Acthar Gel-Related Settlement, Payment Year Six and Seven		62.5				62.5
Settlement of General Unsecured Claims		135				135
Payments for Repurchase of Warrants					4
Issuance of external debt		650		0	0	650	$ 380	0
Acthar Gel-Related Settlement, Payment Year Four and Five		32.5				32.5
Opioid-Related Litigation Settlement, Payment Year One											$ 200
Opioid-Related Litigation Settlement, Final Payment									$ 250
2023 Restructuring Support Agreement, Trust Contingent Value Rights, Share Percentage of Reorganized New Company										5%
2023 Restructuring Support Agreement, Equity Value of Reorganized Debtors										$ 3,776
Class of Warrant or Right, Number of Securities Called by Warrants or Rights	1,036,649						1,036,649
Acthar Gel-Related Settlement, total obligation		260		236.1		260
Warrants and Rights Outstanding, Term	4 years						4 years
Opioid Claimant Trust [Member]
Reorganizations [Line Items]
Opioid-Related Settlement, Year Three through Seven		150				150
2023 Restructuring Support Agreement
Reorganizations [Line Items]
Restructuring Support Agreement, Proposed Long-Term Debt	$ 1,650						$ 1,650
Debt Instrument, Increase (Decrease), Net	2,861.8
StrataGraft PRV
Reorganizations [Line Items]
Other Indefinite-lived Intangible Assets		100				100
StrataGraft PRV | Mallinckrodt
Reorganizations [Line Items]
Proceeds from Sale of Intangible Assets					65
StrataGraft PRV | General Unsecured Claims Trust
Reorganizations [Line Items]
Proceeds from Sale of Intangible Assets					35
Terlipressin [Member]
Reorganizations [Line Items]
Contingent consideration		20				20
Revenue from Customer, Cumulative Threshold		100				100
Reorganization, Chapter 11, Plan Effect Adjustment
Reorganizations [Line Items]
Accrued interest	(31.5)	(13)				(13)	(31.5)
Acthar Gel-Related Settlement, Current	21.4	16.5				16.5	21.4
Payment for Debt Extinguishment or Debt Prepayment Cost		(900)
Contingent consideration		$ (41.8)				$ (41.8)
Ordinary shares, shares issued (in shares)		13,170,932				13,170,932
Reorganization, Chapter 11, Plan Effect Adjustment | StrataGraft PRV | General Unsecured Claims Trust
Reorganizations [Line Items]
Contingent consideration		$ 35				$ 35
Secured Debt
Reorganizations [Line Items]
Debt Instrument, Interest Rate, Increase (Decrease)			200%
Term Loans due Sept 2024 and Feb 2025 [Member]
Reorganizations [Line Items]
Debt Instrument, Interest Rate, Increase (Decrease)			250%
Five Point Six Two Five Percent Note | Senior Notes
Reorganizations [Line Items]
Stated interest rate		5.625%				5.625%
Five Point Five Percent Notes [Member] | Senior Notes
Reorganizations [Line Items]
Stated interest rate		5.50%				5.50%
Debentures
Reorganizations [Line Items]
Increase (Decrease) in Interest Payable, Net						$ 46.5		$ 93
2017 Replacement Term Loan
Reorganizations [Line Items]
Debt instrument, face amount		$ 1,392.9		0	1,374.1	1,392.9
2017 Replacement Term Loan | Reorganization, Chapter 11, Plan Effect Adjustment
Reorganizations [Line Items]
Debt instrument, face amount		1,392.9				1,392.9
2018 Replacement Term Loan
Reorganizations [Line Items]
Debt instrument, face amount		369.7		0	364.8	369.7
2018 Replacement Term Loan | Reorganization, Chapter 11, Plan Effect Adjustment
Reorganizations [Line Items]
Debt instrument, face amount		369.7				369.7
2017 Revolving Credit Facility | Reorganization, Chapter 11, Plan Effect Adjustment
Reorganizations [Line Items]
Payment for Debt Extinguishment or Debt Prepayment Cost		900
Ten Point Zero Percent First Lien Notes [Member]
Reorganizations [Line Items]
Debt instrument, face amount		495		0	495	495
Ten Point Zero Percent First Lien Notes [Member] | Reorganization, Chapter 11, Plan Effect Adjustment
Reorganizations [Line Items]
Debt instrument, face amount		495				495
Ten Point Zero Percent Second Lien Notes (Existing Notes)
Reorganizations [Line Items]
Debt instrument, face amount		322.9				322.9
Ten Point Zero Percent Second Lien Notes (Existing Notes) | Reorganization, Chapter 11, Plan Effect Adjustment
Reorganizations [Line Items]
Debt instrument, face amount		$ 322.9				$ 322.9
Ten Point Zero Percent Second Lien Notes (New 2L Notes)
Reorganizations [Line Items]
Debt instrument, face amount				0	321.9
Increase (Decrease) in Interest Payable, Net							48.5
Ten Point Zero Percent Second Lien Notes (New 2L Notes) | Senior Notes
Reorganizations [Line Items]
Stated interest rate		10%				10%
Eleven Point Five Percent First Lien Senior Secured Notes
Reorganizations [Line Items]
Debt instrument, face amount				0	650
Eleven Point Five Percent First Lien Senior Secured Notes | Reorganization, Chapter 11, Plan Effect Adjustment
Reorganizations [Line Items]
Issuance of external debt		$ 650
Receivables Financing Facility
Reorganizations [Line Items]
Debt instrument, face amount		$ 200		0	0	$ 200
Takeback Term Loans
Reorganizations [Line Items]
Debt instrument, face amount	871.4						871.4
First-Out Takeback Term Loan Due November 2028
Reorganizations [Line Items]
Debt instrument, face amount	229.4			228.8	0		229.4
Second-Out Takeback Term Loan Due November 2028
Reorganizations [Line Items]
Debt instrument, face amount	$ 642			640.4	0		$ 642
Fourteen Point Seven Five Percent Second-Out Takeback Notes
Reorganizations [Line Items]
Stated interest rate	14.75%						14.75%
Debt instrument, face amount	$ 778.6			778.6	$ 0		$ 778.6
Five Point Seven Five Percent Notes | Senior Notes
Reorganizations [Line Items]
Stated interest rate		5.75%				5.75%
Four Point Seven Five Percent Note | Senior Notes
Reorganizations [Line Items]
Stated interest rate		4.75%				4.75%
Maximum
Reorganizations [Line Items]
Remedial cost, estimate				$ 47.9
First Lien Claimholders | 2023 Restructuring Support Agreement
Reorganizations [Line Items]
Restructuring Support Agreement, Equity Share Ownership of Reorganized New Company	92.30%
Second Lien Claimholders | 2023 Restructuring Support Agreement
Reorganizations [Line Items]
Restructuring Support Agreement, Equity Share Ownership of Reorganized New Company	7.70%
Opioid Claimant Trust [Member]
Reorganizations [Line Items]
Opioid-related Settlement		$ 1,725				$ 1,725
Opioid-Related Settlement, Upfront Payment		450				450
Opioid-Related Settlement, Payment Year One and Two		200				200
Opioid-Related Settlement, Year Eight		125				125
Opioid-Related Settlement, Upfront Payment, Prefunded Amount		2.6				2.6
Opioid Claimant Trust [Member] | Reorganization, Chapter 11, Plan Effect Adjustment
Reorganizations [Line Items]
Opioid-related Settlement		1,725				1,725
Medicaid Lawsuit [Member] | Maximum
Reorganizations [Line Items]
Remedial cost, estimate		$ 640				$ 640

Schedule of Interest Expense In

Schedule of Interest Expense Incurred and Paid (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
	Jun. 16, 2022	Dec. 31, 2021
Schedule of Interest Expense Incurred and Paid [Line Items]
Interest Protection Payment, Expense	$ 28.8	$ 63.1
Interest Protection Payment, Paid	$ 28.8	$ 66.7

Fresh-Start Accounting (Details

Fresh-Start Accounting (Details) - USD ($) $ in Millions	Dec. 29, 2023	Nov. 14, 2023	Dec. 30, 2022	Jun. 16, 2022
Reorganizations [Abstract]
Enterprise Value		$ 2,950		$ 5,223
Reorganization, Chapter 11 [Line Items]
Enterprise Value		2,950		5,223
Fair Value, Measurements, Recurring
Reorganization, Chapter 11 [Line Items]
Contingent consideration	$ 14.7	15	$ 7.3
Reorganization, Chapter 11, Plan Effect Adjustment
Reorganization, Chapter 11 [Line Items]
Derivative Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Long-term debt
Contingent consideration				(41.8)
Minimum
Reorganizations [Abstract]
Enterprise Value		2,700		5,200
Reorganization, Chapter 11 [Line Items]
Enterprise Value		2,700		5,200
Minimum | Equity
Reorganizations [Abstract]
Enterprise Value		1,110		563
Reorganization, Chapter 11 [Line Items]
Enterprise Value		1,110		563
Maximum
Reorganizations [Abstract]
Enterprise Value		3,200		5,700
Reorganization, Chapter 11 [Line Items]
Enterprise Value		3,200		5,700
Maximum | Equity
Reorganizations [Abstract]
Enterprise Value		1,610		1,063
Reorganization, Chapter 11 [Line Items]
Enterprise Value		1,610		1,063
Median
Reorganizations [Abstract]
Enterprise Value		2,950		5,450
Reorganization, Chapter 11 [Line Items]
Enterprise Value		2,950		5,450
Median | Equity
Reorganizations [Abstract]
Enterprise Value		1,360		813
Reorganization, Chapter 11 [Line Items]
Enterprise Value		$ 1,360		$ 813

Fresh-Start Accounting - Implie

Fresh-Start Accounting - Implied Fair Value (Details) - USD ($) $ in Millions	Nov. 14, 2023	Jun. 16, 2022
Reorganization, Chapter 11 [Line Items]
Enterprise Value	$ 2,950	$ 5,223
Enterprise Value Adjustments		197
Adjusted Enterprise Value	2,950	5,420
Reorganization Value, Present Value of Discounted Cash Flows of Emerging Entity	1,194.8	2,203.6
Reorganization Value	3,816.9	6,602.3
Median
Reorganization, Chapter 11 [Line Items]
Enterprise Value	2,950	5,450
Cash and Cash Equivalents
Reorganization, Chapter 11 [Line Items]
Adjustments to Enterprise Value		297.9
Non-operating assets, net
Reorganization, Chapter 11 [Line Items]
Adjustments to Enterprise Value	290	178.7
Debt, fair value
Reorganization, Chapter 11 [Line Items]
Adjustments to Enterprise Value	(1,882.7)	(3,067.2)
Other Liabilities, Fair Value
Reorganization, Chapter 11 [Line Items]
Adjustments to Enterprise Value	(162.5)	(625.8)
Other current liabilities
Reorganization, Chapter 11 [Line Items]
Adjustments to Enterprise Value	404.8	522.5
Other Noncurrent Liabilities
Reorganization, Chapter 11 [Line Items]
Adjustments to Enterprise Value	$ 172.1	$ 183.2

Fresh-Start Accounting - Conden

Fresh-Start Accounting - Condensed Consolidated Balance Sheet (Details) - USD ($) $ in Millions			6 Months Ended	11 Months Ended
	Nov. 14, 2023	Jun. 16, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 29, 2023	Jun. 16, 2023	Dec. 30, 2022	Dec. 31, 2021	Dec. 25, 2020
Reorganization, Chapter 11 [Line Items]
Cash and cash equivalents	$ 186.7	$ 297.9	$ 297.9	$ 186.7	$ 262.7		$ 409.5	$ 1,345
Accounts receivable, less allowance for doubtful accounts of $6.5 and $4.4					377.5		405.3
Inventory, Net					982.7		947.6
Total current assets					1,761.8		2,035.8
Property, plant and equipment, net					321.7		457.6
Intangible Assets, Net (Excluding Goodwill)					608.4		2,843.8
Other assets					240.7		201.1
Assets					3,733.6		6,013.8
Current maturities of long-term debt					6.5		44.1
Accounts Payable, Current					100.4		114
Accrued payroll and payroll-related costs					82.8		49.5
Accrued interest					20.1		29
Opioid-Related Litigation Settlement liability					0		200
Accrued and other current liabilities					269.9		290.7
Total current liabilities					501.2		743.8
Long-term debt					1,755.9		3,027.7
Opioid-Related Litigation Settlement liability					0		379.9
Pension and postretirement benefits					40.6		41
Environmental liabilities					35.1		35.8
Deferred income taxes					97.3		224.4
Other income tax liabilities					19.6		18.2
Other Liabilities, Noncurrent					92.5		78.7
Acthar Gel-Related Settlement liability					128.5		75
Liabilities					2,573.4		4,400.1
Additional paid-in capital					1,194.6		2,191
Accumulated Other Comprehensive Income (Loss), Net of Tax					3.6		10.8
Retained deficit					(38.2)		(588.2)
Shareholders' equity	1,194.8	2,203.6	2,203.6	1,194.8	1,160.2		1,613.7	$ 313.4	$ 1,019.2
Total Liabilities and Shareholders' Equity					3,733.6		6,013.8
Cancellation of Predecessor equity			(0.5)	9.2
Opioid Claimant Trust [Member]
Reorganization, Chapter 11 [Line Items]
Opioid-Related Settlement, Payment Year One and Two		200	200
Reorganization, Chapter 11, Predecessor, before Adjustment
Reorganization, Chapter 11 [Line Items]
Cash and cash equivalents	314.1	1,392.6	1,392.6	314.1
Accounts receivable, less allowance for doubtful accounts of $6.5 and $4.4	467.7	387.4	387.4	467.7
Inventory, Net	778.7	375.2	375.2	778.7
Prepaid Expense and Other Assets, Current	149.3	322.6	322.6	149.3
Assets Held-for-sale, Not Part of Disposal Group, Current		0	0
Total current assets	1,709.8	2,477.8	2,477.8	1,709.8
Property, plant and equipment, net	468.6	748.6	748.6	468.6
Intangible Assets, Net (Excluding Goodwill)	2,258.3	5,166.6	5,166.6	2,258.3
Deferred Tax Assets, Net	0	0	0	0
Other assets	222.9	222.8	222.8	222.9
Assets	4,659.6	8,615.8	8,615.8	4,659.6
Current maturities of long-term debt	378.7	1,389.9	1,389.9	378.7
Accounts Payable, Current	93.2	156.4	156.4	93.2
Accrued payroll and payroll-related costs	81.6	71.4	71.4	81.6
Accrued interest	32.2	20.8	20.8	32.2
Taxes Payable	2.7			2.7
Acthar Gel-Related Settlement, Current	0	0	0	0
Opioid-Related Litigation Settlement liability		0	0
Accrued and other current liabilities	222.1	296.1	296.1	222.1
Liabilities Held-for-Sales, Not Part of Disposal Group, Current		0	0
Total current liabilities	810.5	1,934.6	1,934.6	810.5
Long-term debt	0	0	0	0
Opioid-Related Litigation Settlement liability		0	0
Pension and postretirement benefits	39.4	27.6	27.6	39.4
Environmental liabilities	34.6	37.1	37.1	34.6
Deferred income taxes	1.3	20.4	20.4	1.3
Other income tax liabilities	19.6	75.9	75.9	19.6
Other Liabilities, Noncurrent	65.9	68.6	68.6	65.9
Acthar Gel-Related Settlement liability	0	0	0	0
Liabilities subject to compromise	4,932.1	6,402.7	6,402.7	4,932.1
Liabilities	5,903.4	8,566.9	8,566.9	5,903.4
Preferred Stock, Value, Outstanding		0	0
Common Stock, Other Value, Outstanding		0	0
Successor ordinary shares held in treasury at cost, none and none	(0.1)	(1,616.1)	(1,616.1)	(0.1)
Accumulated Other Comprehensive Income (Loss), Net of Tax	10.4	(9.9)	(9.9)	10.4
Retained deficit	(3,454.1)	(3,943.5)	(3,943.5)	(3,454.1)
Shareholders' equity	(1,243.8)	48.9	48.9	(1,243.8)
Total Liabilities and Shareholders' Equity	4,659.6	8,615.8	8,615.8	4,659.6
Reorganization, Chapter 11, Plan Effect Adjustment
Reorganization, Chapter 11 [Line Items]
Cash and cash equivalents	(127.3)	(1,094.7)	(1,094.7)	(127.3)		$ (1,094.7)
Accounts receivable, less allowance for doubtful accounts of $6.5 and $4.4	0	0	0	0
Inventory, Net	0	0	0	0
Prepaid Expense and Other Assets, Current	6.4	75.3	75.3	6.4
Assets Held-for-sale, Not Part of Disposal Group, Current		0	0
Total current assets	(120.9)	(1,019.4)	(1,019.4)	(120.9)
Property, plant and equipment, net	0	0	0	0
Intangible Assets, Net (Excluding Goodwill)	0	0	0	0
Deferred Tax Assets, Net	586.6	0	0	586.6
Other assets	(2.4)	(3.9)	(3.9)	(2.4)
Assets	463.3	(1,023.3)	(1,023.3)	463.3
Current maturities of long-term debt	(370)	(1,355.2)	(1,355.2)	(370)
Accounts Payable, Current	(19.4)	(53.8)	(53.8)	(19.4)
Accrued payroll and payroll-related costs	0	0	0	0
Accrued interest	(31.5)	(13)	(13)	(31.5)
Taxes Payable	0			0
Acthar Gel-Related Settlement, Current	21.4	16.5	16.5	21.4
Opioid-Related Litigation Settlement liability		200	200
Accrued and other current liabilities	31.6	50.8	50.8	31.6
Liabilities Held-for-Sales, Not Part of Disposal Group, Current		35	35
Total current liabilities	(367.9)	(1,119.7)	(1,119.7)	(367.9)
Long-term debt	1,858.9	3,050.9	3,050.9	1,858.9
Opioid-Related Litigation Settlement liability		304.3	304.3
Pension and postretirement benefits	0	27.2	27.2	0
Environmental liabilities	0	0	0	0
Deferred income taxes	0	102.7	102.7	0
Other income tax liabilities	0	0	0	0
Other Liabilities, Noncurrent	7.5	23.6	23.6	7.5
Acthar Gel-Related Settlement liability	214.7	63.2	63.2	214.7
Liabilities subject to compromise	(4,932.1)	(6,402.7)	(6,402.7)	(4,932.1)
Liabilities	(3,218.9)	(3,950.5)	(3,950.5)	(3,218.9)
Successor ordinary shares held in treasury at cost, none and none	0.1	1,616.1	1,616.1	0.1
Additional paid-in capital	1,194.6			1,194.6
Accumulated Other Comprehensive Income (Loss), Net of Tax	0.7	0	0	0.7
Retained deficit	4,686.6	4,725.9	4,725.9	4,686.6
Shareholders' equity	3,682.2	2,927.2	2,927.2	3,682.2
Total Liabilities and Shareholders' Equity	463.3	(1,023.3)	(1,023.3)	463.3
Cancellation of Predecessor equity	2,199.9	4,002.3
Derivative Liability, Current	7.6			7.6
Reorganization, Chapter 11, Fresh-Start Adjustment
Reorganization, Chapter 11 [Line Items]
Cash and cash equivalents	0	0	0	0
Accounts receivable, less allowance for doubtful accounts of $6.5 and $4.4	0	0	0	0
Inventory, Net	257.6	851.8	851.8	257.6
Prepaid Expense and Other Assets, Current	(0.7)	(58.3)	(58.3)	(0.7)
Assets Held-for-sale, Not Part of Disposal Group, Current		100	100
Total current assets	256.9	893.5	893.5	256.9
Property, plant and equipment, net	(150.2)	(299.2)	(299.2)	(150.2)
Intangible Assets, Net (Excluding Goodwill)	(1,633.7)	(2,014.4)	(2,014.4)	(1,633.7)
Deferred Tax Assets, Net	208.5	453.4	453.4	208.5
Other assets	12.5	(23.5)	(23.5)	12.5
Assets	(1,306)	(990.2)	(990.2)	(1,306)
Current maturities of long-term debt	0	0	0	0
Accounts Payable, Current	0	0	0	0
Accrued payroll and payroll-related costs	0	0	0	0
Accrued interest	0	0	0	0
Taxes Payable	0			0
Acthar Gel-Related Settlement, Current	0	0	0	0
Opioid-Related Litigation Settlement liability		0	0
Accrued and other current liabilities	(0.1)	(6.1)	(6.1)	(0.1)
Liabilities Held-for-Sales, Not Part of Disposal Group, Current		0	0
Total current liabilities	(0.1)	(6.1)	(6.1)	(0.1)
Long-term debt	0	(18.4)	(18.4)	0
Opioid-Related Litigation Settlement liability		0	0
Pension and postretirement benefits	0	0	0	0
Environmental liabilities	0	0	0	0
Deferred income taxes	(1.3)	(121.7)	(121.7)	(1.3)
Other income tax liabilities	0	(61.9)	(61.9)	0
Other Liabilities, Noncurrent	27.6	(9.6)	(9.6)	27.6
Acthar Gel-Related Settlement liability	(88.6)	0	0	(88.6)
Liabilities subject to compromise	0	0	0	0
Liabilities	(62.4)	(217.7)	(217.7)	(62.4)
Preferred Stock, Value, Outstanding		0	0
Common Stock, Other Value, Outstanding		0	0
Successor ordinary shares held in treasury at cost, none and none	0	0	0	0
Additional paid-in capital	0			0
Accumulated Other Comprehensive Income (Loss), Net of Tax	(11.1)	9.9	9.9	(11.1)
Retained deficit	(1,232.5)	(782.4)	(782.4)	(1,232.5)
Shareholders' equity	(1,243.6)	(772.5)	(772.5)	(1,243.6)
Total Liabilities and Shareholders' Equity	(1,306)	(990.2)	(990.2)	(1,306)
Reorganization, Chapter11, Post Adjustment, Successor
Reorganization, Chapter 11 [Line Items]
Cash and cash equivalents	186.8	297.9	297.9	186.8
Accounts receivable, less allowance for doubtful accounts of $6.5 and $4.4	467.7	387.4	387.4	467.7
Inventory, Net	1,036.3	1,227	1,227	1,036.3
Prepaid Expense and Other Assets, Current	155	339.6	339.6	155
Assets Held-for-sale, Not Part of Disposal Group, Current		100	100
Total current assets	1,845.8	2,351.9	2,351.9	1,845.8
Property, plant and equipment, net	318.4	449.4	449.4	318.4
Intangible Assets, Net (Excluding Goodwill)	624.6	3,152.2	3,152.2	624.6
Deferred Tax Assets, Net	795.1	453.4	453.4	795.1
Other assets	233	195.4	195.4	233
Assets	3,816.9	6,602.3	6,602.3	3,816.9
Current maturities of long-term debt	8.7	34.7	34.7	8.7
Accounts Payable, Current	73.8	102.6	102.6	73.8
Accrued payroll and payroll-related costs	81.6	71.4	71.4	81.6
Accrued interest	0.7	7.8	7.8	0.7
Taxes Payable	2.7			2.7
Acthar Gel-Related Settlement, Current	21.4	16.5	16.5	21.4
Opioid-Related Litigation Settlement liability		200	200
Accrued and other current liabilities	253.6	340.8	340.8	253.6
Liabilities Held-for-Sales, Not Part of Disposal Group, Current		35	35
Total current liabilities	442.5	808.8	808.8	442.5
Long-term debt	1,858.9	3,032.5	3,032.5	1,858.9
Opioid-Related Litigation Settlement liability		304.3	304.3
Pension and postretirement benefits	39.4	54.8	54.8	39.4
Environmental liabilities	34.6	37.1	37.1	34.6
Deferred income taxes	0	1.4	1.4	0
Other income tax liabilities	19.6	14	14	19.6
Other Liabilities, Noncurrent	101	82.6	82.6	101
Acthar Gel-Related Settlement liability	126.1	63.2	63.2	126.1
Liabilities subject to compromise	0	0	0	0
Liabilities	2,622.1	4,398.7	4,398.7	2,622.1
Preferred Stock, Value, Outstanding		0	0
Common Stock, Other Value, Outstanding		0	0
Successor ordinary shares held in treasury at cost, none and none	0	0	0	0
Additional paid-in capital	1,194.6			1,194.6
Accumulated Other Comprehensive Income (Loss), Net of Tax	0	0	0	0
Retained deficit	0	0	0	0
Shareholders' equity	1,194.8	2,203.6	2,203.6	1,194.8
Total Liabilities and Shareholders' Equity	3,816.9	6,602.3	6,602.3	3,816.9
Predecessor Reorganization
Reorganization, Chapter 11 [Line Items]
Preferred Stock, Value, Outstanding					0		0
Common Stock, Other Value, Outstanding					0		0
Common Stock, Value, Outstanding					$ 0		$ 0.1
Predecessor Reorganization | Reorganization, Chapter 11, Predecessor, before Adjustment
Reorganization, Chapter 11 [Line Items]
Common Stock, Value, Outstanding	0.1	18.9	18.9	0.1
Additional paid-in capital	2,199.9	5,599.5	5,599.5	2,199.9
Predecessor Reorganization | Reorganization, Chapter 11, Plan Effect Adjustment
Reorganization, Chapter 11 [Line Items]
Preferred Stock, Value, Outstanding		0	0
Common Stock, Other Value, Outstanding		0	0
Common Stock, Value, Outstanding	(0.1)	(18.9)	(18.9)	(0.1)
Additional paid-in capital		(5,599.5)	(5,599.5)
Predecessor Reorganization | Reorganization, Chapter 11, Fresh-Start Adjustment
Reorganization, Chapter 11 [Line Items]
Common Stock, Value, Outstanding	0	0	0	0
Additional paid-in capital		0	0
Predecessor Reorganization | Reorganization, Chapter11, Post Adjustment, Successor
Reorganization, Chapter 11 [Line Items]
Common Stock, Value, Outstanding	0	0	0	0
Additional paid-in capital		0	0
Successor, Fresh-Start Adjustments | Reorganization, Chapter 11, Predecessor, before Adjustment
Reorganization, Chapter 11 [Line Items]
Common Stock, Value, Outstanding	0	0	0	0
Additional paid-in capital	0	0	0	0
Successor, Fresh-Start Adjustments | Reorganization, Chapter 11, Plan Effect Adjustment
Reorganization, Chapter 11 [Line Items]
Common Stock, Value, Outstanding	0.2	0.1	0.1	0.2
Additional paid-in capital	(2,199.9)	2,203.5	2,203.5	(2,199.9)
Successor, Fresh-Start Adjustments | Reorganization, Chapter 11, Fresh-Start Adjustment
Reorganization, Chapter 11 [Line Items]
Common Stock, Value, Outstanding	0	0	0	0
Additional paid-in capital	0	0	0	0
Successor, Fresh-Start Adjustments | Reorganization, Chapter11, Post Adjustment, Successor
Reorganization, Chapter 11 [Line Items]
Common Stock, Value, Outstanding	0.2	0.1	0.1	0.2
Additional paid-in capital	$ 0	$ 2,203.5	$ 2,203.5	$ 0

Fresh-Start Accounting - Reorga

Fresh-Start Accounting - Reorganization Adjustments (Details) - USD ($) $ / shares in Units, $ in Millions			1 Months Ended	6 Months Ended		11 Months Ended	12 Months Ended
	Nov. 14, 2023	Jun. 16, 2022	Dec. 29, 2023	Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 30, 2022	Dec. 31, 2021	Jun. 30, 2023	Jun. 16, 2023	Dec. 25, 2020
Reorganization, Chapter 11 [Line Items]
Cash and cash equivalents	$ 186.7	$ 297.9	$ 262.7	$ 409.5	$ 297.9	$ 186.7	$ 409.5	$ 1,345
Debt instrument, face amount			1,647.8	3,534.1			3,534.1
Issuance of external debt		650	0	0	650	380		0
Opioid-Related Settlement, Emergence Payment		447.4			447.4
Opioid-Related Settlement, Gross Amount of Deferred Payment		1,275			1,275
Opioid-Related Litigation Settlement liability			0	200			200
Opioid-Related Litigation Settlement liability			0	379.9			379.9
Stock Issued During Period, Value, New Issues					2,189.7	1,169.7
Adjustments to Additional Paid in Capital, Warrant Issued					(13.9)	(25.1)
Shareholders' equity	$ 1,194.8	2,203.6	$ 1,160.2	$ 1,613.7	2,203.6	1,194.8	$ 1,613.7	313.4			$ 1,019.2
Share Price									$ 1.18
Adjustments to Retained Deficit, Prepaid Success Fee		$ (10.9)			(10.9)
Cancellation of Predecessor equity					$ (0.5)	$ 9.2
Operating Lease, Weighted Average Discount Rate, Percent			8.10%	11.90%			11.90%
Class of Warrant or Right, Exercise Price of Warrants or Rights	$ 99.36	$ 103.40			$ 103.40	$ 99.36
Debtor Reorganization Items, Gain (Loss) on Settlement of Other Claims, Net			$ 0	$ 0	$ 5.4	$ 1,139.5		(0.5)
Debtor Reorganization Items, Write-off of Debt Issuance Costs and Debt Discounts			0	0	0	21.2		23.1
Acthar Gel-Related Settlement, total obligation		$ 260	236.1		260
Acthar Gel-Related Settlement liability			$ 128.5	$ 75			$ 75
Ordinary shares, par value (in usd per share)			$ 0.01	$ 0.01			$ 0.01
Cash Paid, Reorganization items			$ 0.8	$ 18.4	304.1	22.6	$ 333.1
Ordinary Shares
Reorganization, Chapter 11 [Line Items]
Stock Issued During Period, Value, New Issues					0.1	0.2
Shareholders' equity	$ 0.2	$ 0.1	$ 0.2	0.1	0.1	0.2	0.1	18.9			$ 18.8
Cancellation of Predecessor equity					$ (18.9)	$ (0.1)
Successor
Reorganization, Chapter 11 [Line Items]
Ordinary shares, par value (in usd per share)		$ 0.01			$ 0.01
Ordinary shares, shares issued (in shares)	19,696,335	13,170,932			13,170,932	19,696,335
Common Stock, Shares, Outstanding	19,696,335		19,696,335			19,696,335
StrataGraft PRV
Reorganization, Chapter 11 [Line Items]
Other Indefinite-lived Intangible Assets		$ 100			$ 100
Opioid Claimant Trust [Member]
Reorganization, Chapter 11 [Line Items]
Opioid-related Settlement		1,725			1,725
Acthar Gel-Related Settlement
Reorganization, Chapter 11 [Line Items]
Debtor Reorganization Items, Gain (Loss) on Settlement of Other Claims, Net						$ 145
Opioid-related litigation settlement liability
Reorganization, Chapter 11 [Line Items]
Debtor Reorganization Items, Gain (Loss) on Settlement of Other Claims, Net						598.4
Accretion of Debt Discount
Reorganization, Chapter 11 [Line Items]
Debtor Reorganization Items, Gain (Loss) on Settlement of Other Claims, Net						377.6
Receivables Financing Facility
Reorganization, Chapter 11 [Line Items]
Debt instrument, face amount		200	$ 0	0	200		0
Debt Issuance Costs, Gross	$ 1.7					1.7
Long-Term Debt	98.7					98.7
Ten Point Zero Percent Second Lien Notes due 2029
Reorganization, Chapter 11 [Line Items]
Debt instrument, face amount			0	328.3			328.3
Ten Point Zero Percent First Lien Notes [Member]
Reorganization, Chapter 11 [Line Items]
Debt instrument, face amount		495	0	495	495		495
Eleven Point Five Percent First Lien Senior Secured Notes
Reorganization, Chapter 11 [Line Items]
Debt instrument, face amount			0	650			650
Debtor Reorganization Items, Write-off of Debt Issuance Costs and Debt Discounts						18.5
2017 Replacement Term Loan
Reorganization, Chapter 11 [Line Items]
Debt instrument, face amount		1,392.9	0	1,374.1	1,392.9		1,374.1
2018 Replacement Term Loan
Reorganization, Chapter 11 [Line Items]
Debt instrument, face amount		369.7	0	364.8	369.7		364.8
Ten Point Zero Percent Second Lien Notes (New 2L Notes)
Reorganization, Chapter 11 [Line Items]
Debt instrument, face amount			0	321.9			321.9
Debtor-in-Possession Financing
Reorganization, Chapter 11 [Line Items]
Debt instrument, face amount	280					280
First-Out Takeback Term Loan Due November 2028
Reorganization, Chapter 11 [Line Items]
Debt instrument, face amount	229.4		228.8	0		229.4	0
Second-Out Takeback Term Loan Due November 2028
Reorganization, Chapter 11 [Line Items]
Debt instrument, face amount	642		640.4	0		642	0
Fourteen Point Seven Five Percent Second-Out Takeback Notes
Reorganization, Chapter 11 [Line Items]
Debt instrument, face amount	778.6		778.6	0		778.6	$ 0
Ten Point Zero Percent Second Lien Notes (Existing Notes)
Reorganization, Chapter 11 [Line Items]
Debt instrument, face amount		322.9			322.9
Ten Point Zero Percent First Lien Notes Due April 2025
Reorganization, Chapter 11 [Line Items]
Debt instrument, face amount		495			495
Takeback Term Loans
Reorganization, Chapter 11 [Line Items]
Debt instrument, face amount	871.4					871.4
Reorganization, Chapter 11, Plan Effect Adjustment
Reorganization, Chapter 11 [Line Items]
Proceeds from Debt, Net of Issuance Costs		637
Payment for Debt Extinguishment or Debt Prepayment Cost		900
Upfront Payment of the Opioid-Related Litigation Settlement		(447.4)
Upfront Payment of the Acthar Gel-Related Settlement		(17.8)
Payment of Administrative, Priority and Trade Claims		(26.2)
Payment of Professional Fees	(19.4)	43.5
Payment to Fund Professional Fees Escrow	24	(89)
Payment of General Unsecured Claims		(135)
Payment of Noteholder Consent Fees		(19.3)
Payments for Other Fees	33.3	(53.5)
Payment of cash sweep	50.6
Reorganization Adjustments, Cashed Used	127.3	(1,731.7)
Cash and cash equivalents	(127.3)	(1,094.7)			(1,094.7)	(127.3)				$ (1,094.7)
Restricted Cash	24	89			89	24
Prepaid Expense, Reorganization Adjustment		10.9
Other Assets, Reorganization Adjustment	2.4	6.5
Payments for Cure and Standard, Administrative and Priority Payments		25.2			25.2
Payables due to Professional Advisor Success Fees		14.6			14.6
Acthar Gel-Related Settlement, Current	21.4	16.5			16.5	21.4
Opioid-Related Litigation Settlement liability		200			200
Opioid-Related Litigation Settlement liability		304.3			304.3
Contingent consideration		(41.8)			(41.8)
Liabilities Subject to Compromise	4,932.1	6,402.7			6,402.7	4,932.1
Liabilities, Reinstated	(236.2)	(59.8)			(59.8)	(236.2)
Stock Issued During Period, Value, New Issues	(1,169.7)	(2,189.7)
Adjustments to Additional Paid in Capital, Warrant Issued	(25.1)	(13.9)
Issuance of Takeback 2L Notes		(190.2)			(190.2)
Cash payments to settle amounts per the Plan		(601.3)			(601.3)
Total consideration provided to settle amounts per the Plan	(2,729.9)	(5,399.2)			(5,399.2)	(2,729.9)
Gain on settlement of liabilities subject to compromise	1,966	943.7	0	0	(943.7)	(1,966)		0
Additional Paid in Capital, Common Stock	1,169.5	2,189.6			2,189.6	1,169.5
Shareholders' equity	$ 3,682.2	$ 2,927.2			$ 2,927.2	$ 3,682.2
Share Price	$ 60.28	$ 18.50			$ 18.50	$ 60.28
Volatility, Black Scholes Model, Warrants	65%	62.28%			62.28%	65%
Adjustment to Retained Deficit, Professional, Success and Exit Fees	$ (24)	$ (91.6)			$ (91.6)	$ (24)
Adjustments to Retained Deficit, Prepaid Insurance	(20)	(9.2)			(9.2)	(20)
Adjustments to Retained Deficit, Fair Value of First-Out Takeback Term Loans and Related Embedded Derivative	(21.2)					(21.2)
Adjustment to Retained Deficit, Severance Accrual		(5.7)			(5.7)
Adjustment to Retained Deficit, Income Tax Expense on Plan Adjustments	585.9	(102.7)			(102.7)	585.9
Cancellation of Predecessor equity	2,199.9	4,002.3
Reorganization Adjustments to Retained Deficit	$ 4,686.6	$ 4,725.9			$ 4,725.9	$ 4,686.6
Risk-Free Interest Rate, Black Scholes Model, Warrants	4.49%	3.34%			3.34%	4.49%
Derivative Liability, Current	$ 7.6					$ 7.6
Derivative Liability, Noncurrent	7.5					7.5
Acthar Gel-Related Settlement liability	214.7	$ 63.2			$ 63.2	214.7
Ordinary shares, shares issued (in shares)		13,170,932			13,170,932
Reorganization, Chapter 11, Plan Effect Adjustment | Ordinary Shares
Reorganization, Chapter 11 [Line Items]
Stock Issued During Period, Value, New Issues	0.2	$ 0.1
Reorganization, Chapter 11, Plan Effect Adjustment | StrataGraft PRV | General Unsecured Claims Trust
Reorganization, Chapter 11 [Line Items]
Contingent consideration		35			$ 35
Reorganization, Chapter 11, Plan Effect Adjustment | StrataGraft CVR
Reorganization, Chapter 11 [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Contingent Liability	14.9	6.8			6.8	14.9
Reorganization, Chapter 11, Plan Effect Adjustment | Other current liabilities
Reorganization, Chapter 11 [Line Items]
Restructuring Reserve		5.7			5.7
Reinstatement of various successor obligations from LSTC		15.4			15.4
Accrued and Other Current Liabilities, Reorganization Adjustment		29.7			29.7
Accrued and Other Current Liabilities, Reorganization Adjustment		50.8			50.8
Asbestos-related defense cost accrual		16.8			16.8
Reorganization, Chapter 11, Plan Effect Adjustment | Accounts Payable
Reorganization, Chapter 11 [Line Items]
Liabilities Subject to Compromise		(17.7)			(17.7)
Liabilities, Reinstated		(0.1)			(0.1)
Reorganization, Chapter 11, Plan Effect Adjustment | Interest Payable, Current
Reorganization, Chapter 11 [Line Items]
Liabilities Subject to Compromise	(158.8)	(35.2)			(35.2)	(158.8)
Reorganization, Chapter 11, Plan Effect Adjustment | Long-term Debt [Member]
Reorganization, Chapter 11 [Line Items]
Liabilities Subject to Compromise	(3,512.1)	(3,746.2)			(3,746.2)	(3,512.1)
Liabilities, Reinstated	(1,535.1)	(1,778.3)			(1,778.3)	(1,535.1)
Reorganization, Chapter 11, Plan Effect Adjustment | Accrued Environmental Loss Contingencies
Reorganization, Chapter 11 [Line Items]
Liabilities Subject to Compromise		(67.2)			(67.2)
Reorganization, Chapter 11, Plan Effect Adjustment | Acthar Gel-Related Settlement
Reorganization, Chapter 11 [Line Items]
Liabilities Subject to Compromise	(236.1)	(630)			(630)	(236.1)
Liabilities, Reinstated		(79.7)			(79.7)
Reorganization, Chapter 11, Plan Effect Adjustment | Opioid-related litigation settlement liability
Reorganization, Chapter 11 [Line Items]
Liabilities Subject to Compromise	(1,025)	(1,722.4)			(1,722.4)	(1,025)
Liabilities, Reinstated		(504.3)			(504.3)
Reorganization, Chapter 11, Plan Effect Adjustment | Other Liabilities
Reorganization, Chapter 11 [Line Items]
Liabilities Subject to Compromise	(0.1)	(151.6)			(151.6)	(0.1)
Liabilities, Reinstated	(236.1)	(27.3)			(27.3)	(236.1)
Reorganization, Chapter 11, Plan Effect Adjustment | Liability, Defined Benefit Plan, Noncurrent
Reorganization, Chapter 11 [Line Items]
Liabilities Subject to Compromise		(32.4)			(32.4)
Liabilities, Reinstated	(0.1)	(32.4)			(32.4)	(0.1)
Reorganization, Chapter 11, Plan Effect Adjustment | Medicaid Lawsuit [Member]
Reorganization, Chapter 11 [Line Items]
Acthar Gel-Related Settlement, Gross Amount of Deferred Payments		$ 245			$ 245
Discount Rate, Present Value of Future Cash Flows		27.80%			27.80%
Acthar Gel-Related Settlement, Emergence Payment, net of Interest		$ 17.8			$ 17.8
Reorganization, Chapter 11, Plan Effect Adjustment | Opioid Claimant Trust [Member]
Reorganization, Chapter 11 [Line Items]
Opioid-related Settlement		$ 1,725			$ 1,725
Reorganization, Chapter 11, Plan Effect Adjustment | Opioid-related litigation settlement liability
Reorganization, Chapter 11 [Line Items]
Discount Rate, Present Value of Future Cash Flows		27.80%			27.80%
Reorganization, Chapter 11, Plan Effect Adjustment | Insurance Policy Write-off
Reorganization, Chapter 11 [Line Items]
Prepaid Expense, Reorganization Adjustment	17.2
Reorganization, Chapter 11, Plan Effect Adjustment | Directors Compensation Write-off
Reorganization, Chapter 11 [Line Items]
Prepaid Expense, Reorganization Adjustment	0.4
Reorganization, Chapter 11, Plan Effect Adjustment | Receivables Financing Facility
Reorganization, Chapter 11 [Line Items]
Payments of Debt Issuance Costs		$ 2.6
Reorganization, Chapter 11, Plan Effect Adjustment | 2017 and 2018 Replacement Term Loan
Reorganization, Chapter 11 [Line Items]
Debt, Current		34.7			$ 34.7
Reorganization, Chapter 11, Plan Effect Adjustment | Ten Point Zero Percent Second Lien Notes due 2029
Reorganization, Chapter 11 [Line Items]
Debt instrument, face amount		375			375
Reorganization Plan Adjustment		(184.8)			(184.8)
Reorganization, Chapter 11, Plan Effect Adjustment | Ten Point Zero Percent First Lien Notes [Member]
Reorganization, Chapter 11 [Line Items]
Debt instrument, face amount		495			495
Debt Issuance Costs, Gross		5.1			5.1
Reorganization, Chapter 11, Plan Effect Adjustment | Eleven Point Five Percent First Lien Senior Secured Notes
Reorganization, Chapter 11 [Line Items]
Issuance of external debt		650
Reorganization, Chapter 11, Plan Effect Adjustment | Eleven Point Five Percent First Lien Senior Secured Notes | Original Issuance Discount
Reorganization, Chapter 11 [Line Items]
Debt Issuance Costs, Gross		13			13
Reorganization, Chapter 11, Plan Effect Adjustment | Eleven Point Five Percent First Lien Senior Secured Notes | Deferred Debt Issuance Costs
Reorganization, Chapter 11 [Line Items]
Debt Issuance Costs, Gross		9.7			9.7
Reorganization, Chapter 11, Plan Effect Adjustment | 2017 Replacement Term Loan
Reorganization, Chapter 11 [Line Items]
Debt instrument, face amount		1,392.9			1,392.9
Reorganization Plan Adjustment		(169.4)			(169.4)
Reorganization, Chapter 11, Plan Effect Adjustment | 2018 Replacement Term Loan
Reorganization, Chapter 11 [Line Items]
Debt instrument, face amount		369.7			369.7
Reorganization Plan Adjustment		(42.2)			(42.2)
Reorganization, Chapter 11, Plan Effect Adjustment | Ten Point Zero Percent Second Lien Notes (New 2L Notes)
Reorganization, Chapter 11 [Line Items]
Reorganization Plan Adjustment		(95.7)			(95.7)
Reorganization, Chapter 11, Plan Effect Adjustment | Debt
Reorganization, Chapter 11 [Line Items]
Reorganization Plan Adjustment		(492.1)			(492.1)
Reorganization, Chapter 11, Plan Effect Adjustment | First-Out Takeback Term Loan Due November 2028
Reorganization, Chapter 11 [Line Items]
Reorganization Plan Adjustment	15					15
Reorganization, Chapter 11, Plan Effect Adjustment | Second-Out Takeback Term Loan Due November 2028
Reorganization, Chapter 11 [Line Items]
Reorganization Plan Adjustment	46.3					46.3
Reorganization, Chapter 11, Plan Effect Adjustment | Fourteen Point Seven Five Percent Second-Out Takeback Notes
Reorganization, Chapter 11 [Line Items]
Reorganization Plan Adjustment	59.3					59.3
Reorganization, Chapter 11, Plan Effect Adjustment | Secured Debt
Reorganization, Chapter 11 [Line Items]
Reorganization Plan Adjustment	120.6					120.6
Reorganization, Chapter 11, Plan Effect Adjustment | Ten Point Zero Percent Second Lien Notes (Existing Notes)
Reorganization, Chapter 11 [Line Items]
Debt instrument, face amount		322.9			322.9
Reorganization, Chapter11, Post Adjustment, Successor
Reorganization, Chapter 11 [Line Items]
Cash and cash equivalents	186.8	297.9			297.9	186.8
Acthar Gel-Related Settlement, Current	21.4	16.5			16.5	21.4
Opioid-Related Litigation Settlement liability		200			200
Opioid-Related Litigation Settlement liability		304.3			304.3
Liabilities Subject to Compromise	0	0			0	0
Shareholders' equity	1,194.8	2,203.6			2,203.6	1,194.8
Acthar Gel-Related Settlement liability	126.1	63.2			63.2	126.1
Preferred Stock, Value, Outstanding		0			0
Reorganization, Chapter 11, Fresh-Start Adjustment
Reorganization, Chapter 11 [Line Items]
Cash and cash equivalents	0	0			0	0
Acthar Gel-Related Settlement, Current	0	0			0	0
Opioid-Related Litigation Settlement liability		0			0
Opioid-Related Litigation Settlement liability		0			0
Liabilities Subject to Compromise	0	0			0	0
Shareholders' equity	$ (1,243.6)	(772.5)			(772.5)	$ (1,243.6)
Fresh-Start Adjustment, Spare Parts		3.9			3.9
Fresh-Start Adjustments, Debt Issuance Costs		1.1			1.1
Fresh-Start Adjustments, Income Tax Receivables		$ 0.9			$ 0.9
Operating Lease, Weighted Average Discount Rate, Percent	8.10%	11.83%			11.83%	8.10%
Fresh-Start Adjustments, Right-of-Use Assets	$ 12.5	$ 1.6			$ 1.6	$ 12.5
Fresh-Start Adjustments, Asbestos-Related Defense Costs, Current		6.1			6.1
Fresh-Start Adjustments, Asbestos-Related Defense Costs, Non-Current		16.7			16.7
Fresh-Start Adjustments, Lease Liabilities		6.9			6.9
Fresh-Start Adjustments, Unamortized Debt Issuance Costs		5.1			5.1
Fresh-Start Adjustments, Debt, Fair Value		23.5			23.5
Adjustment to Retained Deficit, Inventory	257.6	851.8			851.8	257.6
Adjustment to Retained Deficit, Property, Plant and Equipment	(150.2)	(299.2)			(299.2)	(150.2)
Fresh-Start Adjustments, Intangible assets, net	(1,633.7)	(2,014.4)			(2,014.4)	(1,633.7)
Fresh-Start Adjustments, Acthar Gel-Related Settlement	88.6					88.6
Adjustments to Retained Deficit, Current Asset Held for Sale		100			100
Adjustment to Retained Deficit, Debt		18.4			18.4
Adjustment to Retained Deficit, Other Assets and Liabilities	(15)	(11.2)			(11.2)	(15)
Reorganization Items, net, Loss on Fresh-Start Adjustments	(1,452.7)	(1,354.6)	$ 0	$ 0	1,354.6	1,452.7		$ 0
Fresh-Start Adjustments, Accumulated Other Comprehensive Income	11.1	(9.9)			(9.9)	11.1
Fresh-Start Adjustments, Income Tax Benefit	209.1	582.1			582.1	209.1
Fresh-Start Adjustment, Accumulated Retained Deficit	(1,232.5)	(782.4)			(782.4)	(1,232.5)
Fresh-Start Adjustment, Prepaid Income Taxes		54			54
Fresh-Start Adjustments, Lease Liabilities, Current	0.1					0.1
Fresh-Start Adjustments, Lease Liabilities, Noncurrent	12.7					12.7
Acthar Gel-Related Settlement liability	$ (88.6)	0			0	$ (88.6)
Preferred Stock, Value, Outstanding		0			0
Reorganization, Chapter 11, Fresh-Start Adjustment | Acthar Gel-Related Settlement | Minimum
Reorganization, Chapter 11 [Line Items]
Discount Rate, Present Value of Future Cash Flows	13.30%					13.30%
Reorganization, Chapter 11, Fresh-Start Adjustment | Indemnification Receivable, Current
Reorganization, Chapter 11 [Line Items]
Change in Accounting Policy, Fresh-Start		$ 4.3			$ 4.3
Reorganization, Chapter 11, Fresh-Start Adjustment | Finite-Lived Intangible Assets | Minimum
Reorganization, Chapter 11 [Line Items]
Discount Rate, Present Value of Future Cash Flows	13.50%	13%			13%	13.50%
Reorganization, Chapter 11, Fresh-Start Adjustment | Finite-Lived Intangible Assets | Maximum
Reorganization, Chapter 11 [Line Items]
Discount Rate, Present Value of Future Cash Flows	52.50%	15%			15%	52.50%
Reorganization, Chapter 11, Fresh-Start Adjustment | Indemnification Receivable, Non-Current
Reorganization, Chapter 11 [Line Items]
Change in Accounting Policy, Fresh-Start		$ 16			$ 16
Reorganization, Chapter 11, Fresh-Start Adjustment | Accumulated Other Comprehensive (Loss) Income
Reorganization, Chapter 11 [Line Items]
Fresh-Start Adjustments, AOCI, Income Tax Effects	$ 2.5	0.3			0.3	$ 2.5
Fresh-Start Adjustments, AOCI, Pension Benefits	10	8.1			8.1	10
Fresh-Start Adjustments, AOCI, CTA	2.1	2.1			2.1	2.1
Fresh-Start Adjustments, AOCI, Derivatives	5.7					5.7
Fresh-Start Adjustments, AOCI, Income Tax Benefit	0					0
Reorganization, Chapter 11, Predecessor, before Adjustment
Reorganization, Chapter 11 [Line Items]
Cash and cash equivalents	314.1	1,392.6			1,392.6	314.1
Acthar Gel-Related Settlement, Current	0	0			0	0
Opioid-Related Litigation Settlement liability		0			0
Opioid-Related Litigation Settlement liability		0			0
Liabilities Subject to Compromise	(4,932.1)	(6,402.7)			(6,402.7)	(4,932.1)
Shareholders' equity	$ (1,243.8)	$ 48.9			$ 48.9	$ (1,243.8)
Operating Lease, Weighted Average Discount Rate, Percent	13.20%	8.85%			8.85%	13.20%
Acthar Gel-Related Settlement liability	$ 0	$ 0			$ 0	$ 0
Preferred Stock, Value, Outstanding		$ 0			$ 0

Fresh-Start Accounting - Reor_2

Fresh-Start Accounting - Reorganization Items (Details) - USD ($) $ in Millions			1 Months Ended	6 Months Ended		11 Months Ended	12 Months Ended
	Nov. 14, 2023	Jun. 16, 2022	Dec. 29, 2023	Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 30, 2022	Dec. 31, 2021
Reorganization, Chapter 11 [Line Items]
Cash Paid, Reorganization items			$ 0.8	$ 18.4	$ 304.1	$ 22.6	$ 333.1
Debtor Reorganization Items, Legal and Advisory Professional Fees			4	23.2	161.1	61.7		$ 405.6
Debtor Reorganization Items, Success Fees			0	0	44.3	0		0
Debtor Reorganization Items, Net, Prepaid Expense Write-Off			0	0	9.2	20		0
Debtor Reorganization Items, Acceleration of Predecessor Equity Awards			0	0	0	9		0
Debtor Reorganization Items, Write-off of Debt Issuance Costs and Debt Discounts			0	0	0	21.2		23.1
Debtor Reorganization Items, Gain (Loss) on Settlement of Other Claims, Net			0	0	5.4	1,139.5		(0.5)
Reorganization items, net			4	23.2	630.9	892.7		428.2
Debtor Reorganization Items, Debt Financing			0	0	0	154.6		0
Reorganization, Chapter 11, Plan Effect Adjustment
Reorganization, Chapter 11 [Line Items]
Gain on settlement of liabilities subject to compromise	$ 1,966	$ 943.7	0	0	(943.7)	(1,966)		0
Reorganization, Chapter 11, Fresh-Start Adjustment
Reorganization, Chapter 11 [Line Items]
Reorganization Items, net, Loss on Fresh-Start Adjustments	$ (1,452.7)	$ (1,354.6)	$ 0	$ 0	$ 1,354.6	$ 1,452.7		$ 0

Summary of Significant Accoun_4

Summary of Significant Accounting Policies (Details) - USD ($) $ in Millions	1 Months Ended	6 Months Ended		11 Months Ended	12 Months Ended
	Dec. 29, 2023	Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 31, 2021
Minimum | Completed Technology
Schedule of Significant Accounting Policies [Line Items]
Finite-lived intangible assets - useful lives	1 year
Minimum | Buildings
Schedule of Significant Accounting Policies [Line Items]
Property, plant and equipment, useful life	10 years
Minimum | Leasehold improvements
Schedule of Significant Accounting Policies [Line Items]
Property, plant and equipment, useful life	1 year
Minimum | Capitalized software
Schedule of Significant Accounting Policies [Line Items]
Property, plant and equipment, useful life	1 year
Minimum | Machinery and equipment
Schedule of Significant Accounting Policies [Line Items]
Property, plant and equipment, useful life	1 year
Maximum | Completed Technology
Schedule of Significant Accounting Policies [Line Items]
Finite-lived intangible assets - useful lives	20 years
Maximum | Buildings
Schedule of Significant Accounting Policies [Line Items]
Property, plant and equipment, useful life	45 years
Maximum | Leasehold improvements
Schedule of Significant Accounting Policies [Line Items]
Property, plant and equipment, useful life	20 years
Maximum | Capitalized software
Schedule of Significant Accounting Policies [Line Items]
Property, plant and equipment, useful life	10 years
Maximum | Machinery and equipment
Schedule of Significant Accounting Policies [Line Items]
Property, plant and equipment, useful life	20 years
Shipping Costs
Schedule of Significant Accounting Policies [Line Items]
Shipping costs	$ 3.5	$ 13.9	$ 12.8	$ 22.3	$ 23.6

Revenue from Contracts with C_3

Revenue from Contracts with Customers (Details) - USD ($) $ in Millions	1 Months Ended	6 Months Ended		11 Months Ended	12 Months Ended
	Dec. 29, 2023	Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 31, 2021	Dec. 25, 2020
Disaggregation of Revenue [Line Items]
Revenue Reserves	$ 227.4	$ 294	$ 276.9	$ 250.5	$ 272.8	$ 235.4
Revenue Reserve Provision			715.7		2,166
Capitalized Contract Cost, Gross	0.6	10.3
Revenue Reserve Payments or Credits			(711.6)		(2,128.6)
Net sales	243	1,039.7	874.6	1,622.9	2,208.8
Capitalized Contract Cost, Amortization	0	1	$ 2.9	$ 1.9	$ 6.1
Accrued Medicaid	59	89.3
Accrued rebates	$ 35.1	$ 55.3
Transferred over Time [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Transferred over Time	14.70%	17%	19.20%	16.80%	20.60%
Transferred at Point in Time [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Transferred at Point in Time	85.30%	83%	80.80%	83.20%	79.40%
Royalty [Member]
Disaggregation of Revenue [Line Items]
Net sales	$ 0.1	$ 36.2	$ 34.9	$ 4.3	$ 102.4
Sales Returns and Allowances
Disaggregation of Revenue [Line Items]
Revenue Reserves	14.5	16	18.6	12.8	21.5	26.6
Revenue Reserve Provision	3	7	5.2	9.9	23.7
Revenue Reserve Payments or Credits	(1.3)	(9.6)	(8.1)	(13.1)	(28.8)
Rebates and Chargebacks [Member]
Disaggregation of Revenue [Line Items]
Revenue Reserves	201.6	265.3	250.6	224	241.8	196.5
Revenue Reserve Provision	173	804.4	693.4	1,368.8	2,087.1
Revenue Reserve Payments or Credits	(195.4)	(789.7)	(684.6)	(1,410.1)	(2,041.8)
Other Sales Deductions [Member]
Disaggregation of Revenue [Line Items]
Revenue Reserves	11.3	12.7	7.7	13.7	9.5	$ 12.3
Revenue Reserve Provision	6.9	36.7	17.1	43.3	55.2
Revenue Reserve Payments or Credits	$ (9.3)	$ (31.7)	$ (18.9)	$ (42.3)	$ (58)

Revenue from Contracts with C_4

Revenue from Contracts with Customers Future Performance Obligations (Details) $ in Millions	Dec. 29, 2023 USD ($)
Year One [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	$ 41.6
Year Two [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	23.7
Thereafter [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	$ 4.2

Restructuring and Related Cha_3

Restructuring and Related Charges (Narrative) (Details) - USD ($) $ in Millions	1 Months Ended	6 Months Ended		11 Months Ended	12 Months Ended
	Dec. 29, 2023	Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 31, 2021	Dec. 01, 2021	Feb. 01, 2018
Restructuring Cost and Reserve [Line Items]
Restructuring charges, net	$ 0	$ 11.1	$ 9.6	$ 0.9	$ 26.9
2018 Program | Minimum
Restructuring Cost and Reserve [Line Items]
Mallinckrodt program expected cost range							$ 100
2018 Program | Maximum
Restructuring Cost and Reserve [Line Items]
Mallinckrodt program expected cost range							$ 125
Restructuring Fiscal 2021 Plan | Minimum
Restructuring Cost and Reserve [Line Items]
Mallinckrodt program expected cost range						$ 50
Restructuring Fiscal 2021 Plan | Maximum
Restructuring Cost and Reserve [Line Items]
Mallinckrodt program expected cost range						$ 100

Restructuring and Related Cha_4

Restructuring and Related Charges (Schedule of Restructuring and Related Charges by Segment) (Details) - USD ($) $ in Millions	1 Months Ended	6 Months Ended		11 Months Ended	12 Months Ended
	Dec. 29, 2023	Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 31, 2021
Restructuring Cost and Reserve [Line Items]
Total restructuring and related charges	$ 0	$ 12.1	$ 9.6	$ 1.7	$ 29
Less: accelerated depreciation	0	(1)	0	(0.8)	(2.1)
Restructuring charges, net	0	11.1	9.6	0.9	26.9
Specialty Brands [Member]
Restructuring Cost and Reserve [Line Items]
Total restructuring and related charges	0	0	0	0	0.1
Specialty Generics [Member]
Restructuring Cost and Reserve [Line Items]
Total restructuring and related charges	0	0.8	3.5	0	4.9
Corporate
Restructuring Cost and Reserve [Line Items]
Total restructuring and related charges	$ 0	$ 11.3	$ 6.1	$ 1.7	$ 24

Restructuring and Related Cha_5

Restructuring and Related Charges (Schedule of Net Restructuring and Related Charges) (Details) - USD ($) $ in Millions	1 Months Ended	6 Months Ended		11 Months Ended	12 Months Ended
	Dec. 29, 2023	Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 31, 2021
Restructuring Cost and Reserve [Line Items]
Total restructuring and related charges	$ 0	$ 12.1	$ 9.6	$ 1.7	$ 29
Less: non-cash charges, including accelerated depreciation	0	(2.2)	(3.6)	(0.8)	(6.3)
Total charges expected to be settled in cash	0	9.9	6	0.9	22.7
Restructuring charges, net	0	11.1	9.6	0.9	26.9
2018 Program
Restructuring Cost and Reserve [Line Items]
Total restructuring and related charges	$ 0	$ 12.1	$ 9.6	$ 1.7	$ 29

Restructuring and Related Cha_6

Restructuring and Related Charges (Schedule of Restructuring Reserves by Type of Cost) (Details) - 2018 Program - Continuing Operations - USD ($) $ in Millions	6 Months Ended		11 Months Ended	12 Months Ended
	Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 31, 2021
Restructuring Reserve [Roll Forward]
Beginning Balance	$ 1	$ 10.9	$ 4.6	$ 1
Charges	12.7	7.1	1.3	23.7
Restructuring Reserve, Accrual Adjustment	(2.8)	(1.1)	(0.4)	(1)
Payments for Restructuring	(6.3)	(15.9)	(5.4)	(12.8)
Ending Balance	$ 4.6	$ 1	$ 0.1	$ 10.9

Restructuring and Related Cha_7

Restructuring and Related Charges (Schedule of Restructuring Charges Incurred Cumulative to Date) (Details) $ in Millions	Dec. 29, 2023 USD ($)
Restructuring Cost and Reserve [Line Items]
Restructuring costs incurred cumulative to date	$ 119.3
Specialty Brands [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring costs incurred cumulative to date	3.1
Specialty Generics [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring costs incurred cumulative to date	19.3
Corporate
Restructuring Cost and Reserve [Line Items]
Restructuring costs incurred cumulative to date	$ 96.9

Income Taxes (Narrative) (Detai

Income Taxes (Narrative) (Details) - USD ($) $ in Millions		1 Months Ended	6 Months Ended		11 Months Ended	12 Months Ended
	Jun. 16, 2022	Dec. 29, 2023	Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 29, 2023	Dec. 30, 2022	Dec. 31, 2021
Income Tax Contingency [Line Items]
Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Amount		$ 2.2	$ 4.7	$ (226.5)	$ (56.6)			$ 224.9
Increase (Decrease) Tax Expense (Benefit), Change in Operating Income		(1.4)	(30.2)	(12.8)	(35)			(173.5)
Current Income Tax Expense (Benefit)		(1.4)	(27.1)	(23.9)	41.3			(46.4)
Income Taxes Paid, Net		(0.3)	(3)	(3)	128			160
Deferred Tax Assets, Other		231.3	159.8			$ 231.3	$ 159.8
Tax loss and credit carryforward		3,600.7	3,646			3,600.7	3,646
Unrecognized Tax Benefits, Interest on Income Taxes Accrued		4.2	2.8			4.2	2.8
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	$ 24.8	30.1	24.8	24.8	30.1	30.1	24.8	77
Unrecognized Tax Benefits, Interest on Income Taxes Expense		0	(0.6)	(16.7)	(1.4)			(2.2)
Tax Credit Carryforward, Amount		1.7				1.7
Increase (Decrease) Tax Expense (Benefit) due to opioid-related settlement charge						10.6
Excess in Book over Tax Basis, Foreign Subsidiaries		3.4				3.4
Deferred Income Tax Expense (Benefit)		(6.6)	(24.9)	(473.4)	(319.1)			(59.9)
Benefit from income taxes		(8)	(52)	(497.3)	(277.8)			$ (106.3)
Deferred Tax Assets, Capital Loss Carryforwards		983.5	1,412.6			983.5	1,412.6
Increase (Decrease) Tax Expense (Benefit) due to reorganization items, net					48.9	27.6
Increase (Decrease) Tax Expense (Benefit), Non-restructuring Impairment Charges					11.6	13.2
Deferred Tax Liabilities, Gross		(97.3)	(224.4)			(97.3)	(224.4)
Increase (Decrease) Tax (Benefit), Inventory Step-Up Amortization		3.7	19.7
Increase (Decrease) Tax Expense (Benefit), Settlement liabilities accretion expense		0.2	8.9
Increase (Decrease) Tax Expense (Benefit), Debt accretion expense			6.3
Increase (Decrease) Tax Benefit, Fresh-Start adjustments				128.9
Increase (Decrease) Tax Expense (Benefit), Gain on LSTC adjustments				103.4
Increase (Decrease) Tax Expense (Benefit), Professional & Lender Fees				18.6
Increase (Decrease) Tax Expense Benefit, Fresh-Start Accounting Revaluation of DTA	1,202				242.8
Increase (Decrease) Income Tax Expense (Benefit), Release of UTP	285.3
Increase (Decrease) Tax Expense (Benefit), NOL carryforward reduction	1,209.8
Increase (Decrease) Tax Expense (Benefit), Permanently nondeductible impacts	191.9				139.1
Increase (Decrease) Tax Expense (Benefit), Prepaid income taxes	54
Unrecognized Tax Benefits, Period Increase (Decrease)				$ 306.1
Increase (Decrease) Deferred Tax Assets, Opioid-Related Litigation Settlement Payments						111.7
Increase (Decrease) Deferred Tax Assets, Intangible Assets Amortization						99.7
Increase (Decrease) Deferred Tax Assets, Fresh-Start Adjustment						252.5
Deferred income taxes		801	475.5			801	475.5
Deferred income taxes		0	(0.3)			0	(0.3)
Deferred income tax asset (liability), net		(801)	$ (475.2)			(801)	$ (475.2)
Increase (Decrease) Deferred Tax Assets, Other						110.5
IRELAND
Income Tax Contingency [Line Items]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent			12.50%	12.50%			12.50%	12.50%
Nuclear Imaging
Income Tax Contingency [Line Items]
Benefit from income taxes								$ 5.1
Non-U.K.
Income Tax Contingency [Line Items]
Operating Loss Carryforwards	0.1	6.9	$ 61	$ 0.1	259.6	6.9	$ 61	1.2
Deferred Tax Assets, Operating Loss Carryforwards		3,552.1				3,552.1
Deferred Tax Assets, Operating Loss Carryforwards, Not Subject to Expiration		1,371.9				1,371.9
Deferred Tax Assets, Operating Loss Carryforwards, Subject to Expiration		2,180.2				2,180.2
Deferred Tax Assets, Capital Loss Carryforwards		13.9				13.9
Ireland
Income Tax Contingency [Line Items]
Operating Loss Carryforwards	4.1	0	$ 7.9	$ 4.1	2.9	0	$ 7.9	2.2
Deferred Tax Assets, Operating Loss Carryforwards, Subject to Expiration		46.9				46.9
Deferred Tax Assets, Capital Loss Carryforwards		$ 969.6				$ 969.6
CARES Act
Income Tax Contingency [Line Items]
Proceeds from Income Tax Refunds					141.6			$ 178.8
Chapter 11 Emergence
Income Tax Contingency [Line Items]
Benefit from income taxes	$ 31.6				$ 103.7

Income Taxes (Schedule of Compo

Income Taxes (Schedule of Components of Income from Continuing Operations Before Income Taxes) (Details) - USD ($) $ in Millions	1 Months Ended	6 Months Ended		11 Months Ended	12 Months Ended
	Dec. 29, 2023	Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 31, 2021
Operating Loss Carryforwards [Line Items]
Domestic	$ (0.8)	$ (32.8)	$ 33.7	$ 36.6	$ (33.7)
International	(0.6)	5.7	(57.6)	4.7	(12.7)
Current Income Tax Expense (Benefit)	(1.4)	(27.1)	(23.9)	41.3	(46.4)
Domestic	(6.1)	(44.6)	(82.3)	(300.6)	(59.5)
International	(0.5)	19.7	(391.1)	(18.5)	(0.4)
Deferred Income Tax Expense (Benefit)	(6.6)	(24.9)	(473.4)	(319.1)	(59.9)
Benefit from income taxes	(8)	(52)	(497.3)	(277.8)	(106.3)
Domestic	(46.1)	(359.4)	(2,883.3)	(3,628.8)	(512.2)
International	(0.1)	(290.9)	2,072	1,719.7	(317.6)
Loss from continuing operations before income taxes	(46.2)	(650.3)	(811.3)	(1,909.1)	(829.8)
Ireland
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards	0	7.9	4.1	2.9	2.2
Non-U.K.
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards	$ 6.9	$ 61	$ 0.1	$ 259.6	$ 1.2

Income Taxes (Schedule of Signi

Income Taxes (Schedule of Significant Components of Income Taxes Related to Continuing Operations) (Details) - USD ($) $ in Millions	1 Months Ended	6 Months Ended		11 Months Ended	12 Months Ended
	Dec. 29, 2023	Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 31, 2021
Current:
Domestic	$ (0.8)	$ (32.8)	$ 33.7	$ 36.6	$ (33.7)
International	(0.6)	5.7	(57.6)	4.7	(12.7)
Current income tax (benefit) provision	(1.4)	(27.1)	(23.9)	41.3	(46.4)
Deferred:
Domestic	(6.1)	(44.6)	(82.3)	(300.6)	(59.5)
International	(0.5)	19.7	(391.1)	(18.5)	(0.4)
Deferred income tax (benefit) provision	(6.6)	(24.9)	(473.4)	(319.1)	(59.9)
Provision for (benefit from) income taxes	(8)	(52)	(497.3)	(277.8)	(106.3)
Increase (Decrease) Tax Expense (Benefit), Change in Operating Income	$ (1.4)	$ (30.2)	$ (12.8)	$ (35)	$ (173.5)

Income Taxes (Schedule of Recon

Income Taxes (Schedule of Reconciliation of Income Taxes at Statutory Rate and Tax Provision) (Details) - USD ($) $ in Millions		1 Months Ended	6 Months Ended			11 Months Ended	12 Months Ended
	Jun. 16, 2022	Dec. 29, 2023	Dec. 30, 2022		Jun. 16, 2022	Nov. 14, 2023	Dec. 29, 2023	Dec. 30, 2022	Dec. 31, 2021
Income Taxes [Line Items]
Income tax expense (benefit), intercompany financing and legal entity reorganization		$ (6.6)	$ (24.9)		$ (473.4)	$ (319.1)			$ (59.9)
Benefit for income taxes at domestic statutory income tax rate (1)		(5.8)	(81.3)	[1]	(101.4)	(238.6)			(103.7)	[1]
Adjustments to reconcile to income tax provision:
Rate difference between non-U.S. and U.S. jurisdictions		2.2	4.7		(226.5)	(56.6)			224.9
Valuation allowances (5)		0.1	25.9		(600.8)	44			189.7
Adjustments to accrued income tax liabilities and uncertain tax positions		0	0	[2]	0	0			(9.7)	[2]
Credits, principally research		0	0		(0.9)	(1.9)			(4.7)
Permanently nondeductible and nontaxable items		(0.2)	3.1		(1.7)	3.2			9.8
Effective Income Tax Rate Reconciliation, Disposition of Business, Amount		0	4.7		0	0			0
Other		0.1	(1.4)		(3.1)	0.6			0.3
Income tax benefit, Legal Reorganization		0	0		0	(44.7)			0
Effective Income Tax Rate Reconciliation, Reorganization Items, net		0	1.7		15.7	6.7			36.9
Provision for (benefit from) income taxes		(8)	(52)		(497.3)	(277.8)			(106.3)
Increase (Decrease) Tax Expense (Benefit) due to opioid-related settlement charge							$ 10.6
Increase (Decrease) Tax Expense (Benefit), Change in Operating Income		(1.4)	(30.2)		(12.8)	(35)			(173.5)
Increase (Decrease) Tax Expense (Benefit) due to reorganization items, net						48.9	27.6
Increase (Decrease) Tax Expense (Benefit), Non-restructuring Impairment Charges						11.6	$ 13.2
Effective income tax rate reconciliation, pension plan settlement		0	0		(31.6)	(103.7)			$ 0
Increase (Decrease) Tax (Benefit), Inventory Step-Up Amortization		3.7	19.7
Increase (Decrease) Tax Expense (Benefit), Settlement liabilities accretion expense		0.2	$ 8.9
Increase (Decrease) Tax Expense (Benefit), Debt amortization expense		$ 0.3
Increase (Decrease) Tax Expense (Benefit) Liabilities Management & Separation Costs						15.7
Increase (Decrease) Tax Expense Benefit, Fresh-Start Accounting Revaluation of DTA	$ 1,202					242.8
Increase (Decrease) Income Tax Expense (Benefit), Release of UTP	285.3
Increase (Decrease) Tax Expense (Benefit), NOL carryforward reduction	1,209.8
Increase (Decrease) Tax Expense (Benefit), Permanently nondeductible impacts	191.9					139.1
Increase (Decrease) Tax Expense (Benefit), Prepaid income taxes	54
Alleviation of Substantial Doubt
Adjustments to reconcile to income tax provision:
Valuation allowances (5)					$ 512.1
Chapter 11 Emergence
Adjustments to reconcile to income tax provision:
Provision for (benefit from) income taxes	$ 31.6					$ 103.7
IRELAND
Income Taxes [Line Items]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent			12.50%		12.50%			12.50%	12.50%
[1] The statutory tax rate reflects the Irish statutory tax rate of 12.5%. Includes interest and penalties on accrued income tax liabilities and uncertain tax positions.

Income Taxes (Schedule of Unrec

Income Taxes (Schedule of Unrecognized Tax Benefit Activity) (Details) - USD ($) $ in Millions	1 Months Ended	6 Months Ended		11 Months Ended	12 Months Ended
	Dec. 29, 2023	Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 31, 2021
Income Tax Contingency [Line Items]
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	$ 30.1	$ 24.8	$ 24.8	$ 30.1	$ 77
Unrecognized Tax Benefits, Interest on Income Taxes Expense	0	0.6	16.7	1.4	2.2
Reconciliation of Unrecognized Tax Benefits [Roll Forward]
Balance at beginning of period	33.3	24.8	333.5	24.8	349
Additions related to current year tax positions	0	0	0	8.5	0
Additions related to prior period tax positions	0	0	0	0	9.3
Reductions related to prior period tax positions	0	0	(306.1)	0	(2.8)
Settlements	0	0	(2.6)	0	(0.2)
Lapse of statutes of limitations	0	0	0	0	(21.8)
Balance at end of period	$ 33.3	$ 24.8	$ 24.8	$ 33.3	$ 333.5

Income Taxes (Schedule of Unr_2

Income Taxes (Schedule of Unrecognized Tax Benefits Balance Sheet Location) (Details) - USD ($) $ in Millions	Dec. 29, 2023	Nov. 14, 2023	Dec. 30, 2022	Jun. 16, 2022	Dec. 31, 2021	Dec. 25, 2020
Income Tax Contingency [Line Items]
Unrecognized Tax Benefits	$ 33.3	$ 33.3	$ 24.8	$ 24.8	$ 333.5	$ 349
Other Income Tax Liabilities
Income Tax Contingency [Line Items]
Unrecognized Tax Benefits	15.4		15.4
Liabilities, Total [Member]
Income Tax Contingency [Line Items]
Unrecognized Tax Benefits	33.3		24.8
Deferred tax asset, non-current
Income Tax Contingency [Line Items]
Unrecognized Tax Benefits	$ 17.9		$ 9.4

Income Taxes (Schedule of Incom

Income Taxes (Schedule of Income Taxes Payable) (Details) - USD ($) $ in Millions	Dec. 29, 2023	Dec. 30, 2022
Operating Loss Carryforwards [Line Items]
Other income tax liabilities	$ 19.6	$ 18.2
Total income taxes payable	21.3	21.8
Accrued and Other Current Liabilities
Operating Loss Carryforwards [Line Items]
Accrued and other current liabilities	1.7	3.6
Other Income Tax Liabilities
Operating Loss Carryforwards [Line Items]
Other income tax liabilities	$ 19.6	$ 18.2

Income Taxes (Schedule of Inc_2

Income Taxes (Schedule of Income Tax Receivables and Other Assets) (Details) - USD ($) $ in Millions	Dec. 29, 2023	Dec. 30, 2022
Income Tax Disclosure [Abstract]
Prepaid expenses and other current assets	$ 11.5	$ 179.5

Income Taxes (Schedule of Defer

Income Taxes (Schedule of Deferred Taxes Activity) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 29, 2023	Dec. 30, 2022
Deferred tax assets:
Tax loss and credit carryforward	$ 3,600.7	$ 3,646
Deferred Tax Assets, Capital Loss Carryforwards	983.5	1,412.6
Deferred Tax Assets, Opioid-related litigation settlement	0	111.7
Deferred Tax Assets, Goodwill and Intangible Assets	571.5	278.4
Deferred Tax Asset, Interest Carryforward	95.1	84
Other	231.3	159.8
Total deferred tax assets, gross	5,482.1	5,692.5
Deferred tax liabilities:
Investment in partnership	(68.7)	(67.4)
Deferred Tax Liabilities, Other	(28.6)	(157)
Total deferred tax liabilities, gross	(97.3)	(224.4)
Net deferred tax asset before valuation allowances	5,384.8	5,468.1
Valuation allowances	(4,583.8)	(4,992.9)
Deferred income tax asset (liability), net	801	$ 475.2
Increase (Decrease) Deferred Tax Assets, Capital Tax Loss Carryforwards	434.3
Increase (Decrease) Deferred Tax Assets, Other	$ 110.5

Earnings (Loss) per Share (Deta

Earnings (Loss) per Share (Details) - shares shares in Millions	1 Months Ended	6 Months Ended		11 Months Ended	12 Months Ended
	Dec. 29, 2023	Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 30, 2022	Dec. 31, 2021
Earnings (Loss) per Share [Abstract]
Weighted Average Number of Shares Outstanding, Basic	19.7	13.2	84.8	13.3		84.7
Weighted-average shares for diluted earnings (loss) per share (in shares)	19.7	13.2	84.8	13.3		84.7
Antidilutive securities excluded from weighted-average shares (in shares)	1	0	0.5	0	5.2

Earnings (Loss) per Share Sched

Earnings (Loss) per Share Schedule of Earnings per Share Basic and Diluted (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	1 Months Ended	6 Months Ended		11 Months Ended	12 Months Ended
	Dec. 29, 2023	Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 31, 2021
Earnings Per Share [Abstract]
Income (loss) from continuing operations	$ (38.2)	$ (598.3)	$ (314)	$ (1,631.3)	$ (723.5)
Income (loss) from discontinued operations, net of income taxes	$ 0	$ 0.2	$ 0.9	$ 0	$ 6.1
Weighted Average Number of Shares Outstanding, Basic	19.7	13.2	84.8	13.3	84.7
Weighted Average Number of Shares Outstanding, Diluted	19.7	13.2	84.8	13.3	84.7
Loss from continuing operations	$ (1.94)	$ (45.43)	$ (3.70)	$ (122.75)	$ (8.54)
Income (Loss) from Discontinued Operations, Per Basic Share	0	0.02	0.01	0	0.07
Earnings Per Share, Basic	(1.94)	(45.41)	(3.69)	(122.75)	(8.47)
Loss from continuing operations	(1.94)	(45.43)	(3.70)	(122.75)	(8.54)
Income (Loss) from Discontinued Operations, Per Diluted Share	0	0.02	0.01	0	0.07
Earnings Per Share, Diluted	$ (1.94)	$ (45.41)	$ (3.69)	$ (122.75)	$ (8.47)

Inventories (Details)

Inventories (Details) - USD ($) $ in Millions	Dec. 29, 2023	Dec. 30, 2022
Inventory, Net [Abstract]
Raw materials	$ 98	$ 80.2
Work in process	501.8	552.1
Finished goods	382.9	315.3
Inventories	$ 982.7	$ 947.6

Property, Plant and Equipment_2

Property, Plant and Equipment (Narrative) (Details) - USD ($) $ in Millions	1 Months Ended	6 Months Ended		11 Months Ended	12 Months Ended
	Dec. 29, 2023	Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 31, 2021
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 331.3	$ 485
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	9.6	27.4
Depreciation	$ 9.6	$ 28.8	$ 40	$ 40.7	$ 94.7

Property, Plant and Equipment_3

Property, Plant and Equipment (Schedule of Property, Plant and Equipment) (Details) - USD ($) $ in Millions	1 Months Ended	6 Months Ended		11 Months Ended	12 Months Ended
	Dec. 29, 2023	Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 31, 2021
Property, Plant and Equipment [Line Items]
Depreciation	$ 9.6	$ 28.8	$ 40	$ 40.7	$ 94.7
Property, plant and equipment, gross	331.3	485
Less: accumulated depreciation	(9.6)	(27.4)
Property, plant and equipment, net	321.7	457.6
Land
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	37.7	51
Buildings
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	94.6	127.2
Capitalized Software
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	1.9	17.5
Machinery and Equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	136.3	216.8
Construction in Progress
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 60.8	$ 72.5

Leases (Details)

Leases (Details) - USD ($) $ in Millions	1 Months Ended	6 Months Ended		11 Months Ended	12 Months Ended
	Dec. 29, 2023	Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 31, 2021
Leases [Abstract]
Operating Lease, Right-of-Use Asset	$ 50.9	$ 38.1
Operating Lease, Liability, Current	10.5	10.3
Operating Lease, Liability, Noncurrent	$ 44.8	$ 30.4
Operating Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Other Liabilities	Other Liabilities
Operating Lease, Cost	$ 1.8	$ 7.9	$ 8.7	$ 15	$ 19.6
Short-term Lease, Cost	0.5	1.6	0.4	0.9	1.1
Variable Lease, Cost	0	1.5	1.2	2.3	2.4
Lease, Cost	$ 2.3	$ 11	10.3	18.2	23.1
Operating Lease, Weighted Average Remaining Lease Term	7 years 4 months 24 days	6 years 8 months 12 days
Operating Lease, Weighted Average Discount Rate, Percent	8.10%	11.90%
Lessee, Operating Lease, Liability, Payments, Due Next Twelve Months	$ 14.4
Lessee, Operating Lease, Liability, Payments, Due Year Two	13.2
Operating Lease, Liability	55.3	$ 40.7
Lessee, Operating Lease, Liability, Payments, Due Year Three	8.9
Lessee, Operating Lease, Liability, Payments, Due Year Four	6.9
Lessee, Operating Lease, Liability, Payments, Due Year Five	6.6
Lessee, Operating Lease, Liability, Payments, Due after Year Five	24.7
Lessee, Operating Lease, Liability, Payments, Due	74.7
Lessee, Operating Lease, Liability, Undiscounted Excess Amount	(19.4)
Operating Lease, Payments	2.4	9.2	9.4	14.6	20.4
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability	0	7.1	$ 13.4	$ 13.2	$ 2.6
Lessee, Lease, Description [Line Items]
Operating Lease, Liability, Current	10.5	10.3
Operating Lease, Liability, Noncurrent	44.8	30.4
Operating Lease, Liability	$ 55.3	$ 40.7
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Other assets	Other assets
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Accrued and other current liabilities	Accrued and other current liabilities
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Other Liabilities, Noncurrent	Other Liabilities, Noncurrent

Goodwill and Intangible Asset_2

Goodwill and Intangible Assets Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	6 Months Ended		11 Months Ended	12 Months Ended
	Dec. 29, 2023	Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 31, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Intangible asset amortization	$ 16.2	$ 318.7	$ 281.8	$ 449.6	$ 581.1
Finite-Lived Intangible Assets [Line Items]
Other Asset Impairment Charges	2.6	0	0	135.9	154.9
Intangible Assets, Net (Excluding Goodwill)	608.4	2,843.8
Intangible asset amortization	$ 16.2	$ 318.7	$ 281.8	$ 449.6	$ 581.1
Loss from continuing operations	$ (1.94)	$ (45.43)	$ (3.70)	$ (122.75)	$ (8.54)
Finite-lived intangible assets, gross				$ 624.6
Completed Technology
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	$ 624.6	$ 3,041.2
Reorganization, Chapter11, Post Adjustment, Successor
Finite-Lived Intangible Assets [Line Items]
Intangible Assets, Net (Excluding Goodwill)			$ 3,152.2	624.6
Specialty Brands [Member]
Finite-Lived Intangible Assets [Line Items]
Other Asset Impairment Charges					$ 154.9
Specialty Generics [Member]
Finite-Lived Intangible Assets [Line Items]
Other Asset Impairment Charges				85.8
StrataGraft [Member] | Specialty Brands [Member]
Finite-Lived Intangible Assets [Line Items]
Other Asset Impairment Charges				50.1
StrataGraft PRV
Finite-Lived Intangible Assets [Line Items]
Other Indefinite-lived Intangible Assets			100
StrataGraft PRV | Mallinckrodt
Finite-Lived Intangible Assets [Line Items]
Proceeds from Sale of Intangible Assets		65
StrataGraft PRV | General Unsecured Claims Trust
Finite-Lived Intangible Assets [Line Items]
Proceeds from Sale of Intangible Assets		$ 35
Amitiza
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross				12.3
Amitiza | Change in Accounting Method Accounted for as Change in Estimate
Goodwill and Intangible Assets Disclosure [Abstract]
Intangible asset amortization			21.7
Finite-Lived Intangible Assets [Line Items]
Intangible asset amortization			$ 21.7
Loss from continuing operations			$ 0.26
Amitiza | Specialty Generics [Member]
Finite-Lived Intangible Assets [Line Items]
Other Asset Impairment Charges					90.4
Terlivaz
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross				$ 68.1
MNK-6105 [Member] | Specialty Brands [Member]
Finite-Lived Intangible Assets [Line Items]
Other Asset Impairment Charges					$ 64.5

Goodwill and Intangible Asset_3

Goodwill and Intangible Assets (Schedule Of Intangible Assets) (Details) - USD ($) $ in Millions	1 Months Ended	6 Months Ended		11 Months Ended	12 Months Ended
	Dec. 29, 2023	Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 31, 2021
Schedule of Intangible Asset by Major Class [Line Items]
Other Asset Impairment Charges	$ 2.6	$ 0	$ 0	$ 135.9	$ 154.9
Intangible asset amortization	16.2	318.7	281.8	449.6	581.1
Amortizable:
Finite-lived intangible assets, gross				624.6
Non-Amortizable:
Asset Impairment Charges	3.8	0	$ 0	179.9	$ 154.9
In-process research and development
Non-Amortizable:
Indefinite-lived intangible assets, gross	0	121.3
Completed Technology
Amortizable:
Finite-lived intangible assets, gross	624.6	3,041.2
Accumulated amortization	$ 16.2	$ 318.7
Acthar Gel
Amortizable:
Finite-lived intangible assets, gross				$ 110
Non-Amortizable:
Finite-lived intangible assets - useful lives				10 years
Acthar Gel | Finite-Lived Intangible Assets
Non-Amortizable:
Discount Rate, Present Value of Future Cash Flows				52.30%
Therakos
Amortizable:
Finite-lived intangible assets, gross				$ 129.4
Non-Amortizable:
Finite-lived intangible assets - useful lives				9 years
Therakos | Finite-Lived Intangible Assets
Non-Amortizable:
Discount Rate, Present Value of Future Cash Flows				51.50%
Amitiza
Amortizable:
Finite-lived intangible assets, gross				$ 12.3
Non-Amortizable:
Finite-lived intangible assets - useful lives				1 year
Amitiza | Finite-Lived Intangible Assets
Non-Amortizable:
Discount Rate, Present Value of Future Cash Flows				51.50%
Inomax
Amortizable:
Finite-lived intangible assets, gross				$ 41.3
Non-Amortizable:
Finite-lived intangible assets - useful lives				8 years
Inomax | Finite-Lived Intangible Assets
Non-Amortizable:
Discount Rate, Present Value of Future Cash Flows				51.50%
Generics
Amortizable:
Finite-lived intangible assets, gross				$ 186.7
Non-Amortizable:
Finite-lived intangible assets - useful lives				18 years
Generics | Finite-Lived Intangible Assets
Non-Amortizable:
Discount Rate, Present Value of Future Cash Flows				14.10%
APAP
Amortizable:
Finite-lived intangible assets, gross				$ 76.8
Non-Amortizable:
Finite-lived intangible assets - useful lives				20 years
APAP | Finite-Lived Intangible Assets
Non-Amortizable:
Discount Rate, Present Value of Future Cash Flows				13.50%
Terlivaz
Amortizable:
Finite-lived intangible assets, gross				$ 68.1
Non-Amortizable:
Finite-lived intangible assets - useful lives				5 years 6 months
Terlivaz | Finite-Lived Intangible Assets
Non-Amortizable:
Discount Rate, Present Value of Future Cash Flows				52.50%

Goodwill and Intangible Asset_4

Goodwill and Intangible Assets (Schedule of Future Amortization Expense, Intangible Assets) (Details) $ in Millions	Dec. 29, 2023 USD ($)
Finite-Lived Intangible Assets [Line Items]
Fiscal 2020	$ 90.3
Fiscal 2021	74.8
Fiscal 2022	68.4
Fiscal 2023	62
Fiscal 2024	$ 55.6

Debt (Narrative) (Details)

Debt (Narrative) (Details) - USD ($) $ in Millions			1 Months Ended	6 Months Ended		11 Months Ended	12 Months Ended
	Nov. 14, 2023	Jun. 16, 2022	Dec. 29, 2023	Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 31, 2021
Debt Instrument [Line Items]
Debt instrument, face amount			$ 1,647.8	$ 3,534.1
Long-term Debt, Gross			1,758.8	3,048.5
Debt Issuance Costs, Net			2.9	20.8
Repayments of Debt			102.2	50.1	$ 904.6	$ 102.6	$ 137.5
Debtor Reorganization Items, Write-off of Debt Issuance Costs and Debt Discounts			0	0	0	21.2	23.1
Issuance of external debt		$ 650	0	0	650	380	0
Derivative Liability	$ 15.1					15.1
Debtor Reorganization Items, Gain (Loss) on Settlement of Other Claims, Net			0	0	5.4	1,139.5	$ (0.5)
Accretion of Debt Discount
Debt Instrument [Line Items]
Debtor Reorganization Items, Gain (Loss) on Settlement of Other Claims, Net						377.6
Ten Point Zero Percent First Lien Notes [Member]
Debt Instrument [Line Items]
Debt instrument, face amount		495	0	495	495
Ten Point Zero Percent First Lien Notes [Member] | Reorganization, Chapter 11, Plan Effect Adjustment
Debt Instrument [Line Items]
Debt instrument, face amount		495			495
Debt Issuance Costs, Gross		5.1			5.1
Term Loans due Sept 2024 and Feb 2025 [Member]
Debt Instrument [Line Items]
Extinguishment of Debt, Amount	1,716.8
Ten Point Zero Percent Second Lien Notes (New 2L Notes)
Debt Instrument [Line Items]
Debt instrument, face amount			0	321.9
Extinguishment of Debt, Amount	321.9
2017 Replacement Term Loan
Debt Instrument [Line Items]
Debt instrument, face amount		1,392.9	0	1,374.1	1,392.9
Debt Issuance Costs, Net			0	0
2017 Replacement Term Loan | Reorganization, Chapter 11, Plan Effect Adjustment
Debt Instrument [Line Items]
Debt instrument, face amount		1,392.9			1,392.9
2018 Replacement Term Loan
Debt Instrument [Line Items]
Debt instrument, face amount		369.7	0	364.8	369.7
Debt Issuance Costs, Net			0	0
2018 Replacement Term Loan | Reorganization, Chapter 11, Plan Effect Adjustment
Debt Instrument [Line Items]
Debt instrument, face amount		369.7			369.7
Eleven Point Five Percent First Lien Senior Secured Notes
Debt Instrument [Line Items]
Debt instrument, face amount			0	650
Extinguishment of Debt, Amount	650
Debt Issuance Costs, Net			0	20.8
Debtor Reorganization Items, Write-off of Debt Issuance Costs and Debt Discounts						18.5
Eleven Point Five Percent First Lien Senior Secured Notes | Reorganization, Chapter 11, Plan Effect Adjustment
Debt Instrument [Line Items]
Issuance of external debt		650
Ten Point Zero Percent Second Lien Notes due 2029
Debt Instrument [Line Items]
Debt instrument, face amount			0	328.3
Extinguishment of Debt, Amount	328.3
Debt Issuance Costs, Net			0	0
Ten Point Zero Percent Second Lien Notes due 2029 | Reorganization, Chapter 11, Plan Effect Adjustment
Debt Instrument [Line Items]
Debt instrument, face amount		375			375
Receivables Financing Facility
Debt Instrument [Line Items]
Debt instrument, face amount		200	0	0	200
Debt Issuance Costs, Net			2.9	0
Debt Issuance Costs, Gross	1.7					1.7
Ten Point Zero Percent First Lien Notes Due April 2025
Debt Instrument [Line Items]
Debt instrument, face amount		$ 495			$ 495
Extinguishment of Debt, Amount	495
First-Out Takeback Term Loan Due November 2028
Debt Instrument [Line Items]
Debt instrument, face amount	$ 229.4		$ 228.8	0		$ 229.4
Long-term Debt, Weighted Average Interest Rate, at Point in Time			11.40%
Debt Issuance Costs, Net			$ 0	0
Debt Instrument, Stated Interest Rate, Amortization	1%					1%
Second-Out Takeback Term Loan Due November 2028
Debt Instrument [Line Items]
Debt instrument, face amount	$ 642		$ 640.4	0		$ 642
Long-term Debt, Weighted Average Interest Rate, at Point in Time			13.40%
Debt Issuance Costs, Net			$ 0	0
Debt Instrument, Stated Interest Rate, Amortization	1%					1%
Fourteen Point Seven Five Percent Second-Out Takeback Notes
Debt Instrument [Line Items]
Debt instrument, face amount	$ 778.6		778.6	0		$ 778.6
Stated interest rate	14.75%					14.75%
Debt Issuance Costs, Net			0	0
Takeback Term Loans
Debt Instrument [Line Items]
Debt instrument, face amount	$ 871.4					$ 871.4
Excess Cash Flow Threshold	$ 100					$ 100
Senior Notes | Five Point Six Two Five Percent Note
Debt Instrument [Line Items]
Stated interest rate		5.625%			5.625%
Senior Notes | Five Point Five Percent Notes [Member]
Debt Instrument [Line Items]
Stated interest rate		5.50%			5.50%
Senior Notes | Ten Point Zero Percent Second Lien Notes (New 2L Notes)
Debt Instrument [Line Items]
Stated interest rate		10%			10%
Secured Debt | Ten Point Zero Percent First Lien Notes [Member]
Debt Instrument [Line Items]
Debt Issuance Costs, Net			0	0
Secured Debt | Ten Point Zero Percent Second Lien Notes (New 2L Notes)
Debt Instrument [Line Items]
Debt Issuance Costs, Net			$ 0	$ 0
Alternate Base Rate | First-Out Takeback Term Loan Due November 2028
Debt Instrument [Line Items]
Variable interest rate	6.50%
Alternate Base Rate | Second-Out Takeback Term Loan Due November 2028
Debt Instrument [Line Items]
Variable interest rate	8.50%
Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate | First-Out Takeback Term Loan Due November 2028
Debt Instrument [Line Items]
Variable interest rate	7.50%
Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate | First-Out Takeback Term Loan Due November 2028 | Minimum
Debt Instrument [Line Items]
Variable interest rate		450%
Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate | Second-Out Takeback Term Loan Due November 2028
Debt Instrument [Line Items]
Variable interest rate	950%
Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate | Second-Out Takeback Term Loan Due November 2028 | Minimum
Debt Instrument [Line Items]
Variable interest rate		4.50%

Debt (Schedule of Long term deb

Debt (Schedule of Long term debt) (Details) - USD ($) $ in Millions	Nov. 14, 2023	Dec. 29, 2023	Dec. 30, 2022	Jun. 16, 2022
Long-term Debt, Current Maturities [Abstract]
Long-term Debt, Current Maturities		$ (6.5)	$ (44.1)
Long-term Debt, Excluding Current Maturities [Abstract]
Long-term Debt, Gross		1,758.8	3,048.5
Debt Issuance Costs, Noncurrent, Net		2.9	20.8
Debt Issuance Costs, Net		2.9	20.8
Debt, Long-term and Short-term, Combined Amount		1,765.3	3,092.6
Debt Issuance Costs, Current, Net		0	0
Debt instrument, face amount		1,647.8	3,534.1
Long-term Debt, Excluding Current Maturities		1,641.3	3,490
Ten Point Zero Percent First Lien Notes [Member]
Long-term Debt, Excluding Current Maturities [Abstract]
Secured Debt		0	475.9
Debt instrument, face amount		0	495	$ 495
Ten Point Zero Percent Second Lien Notes (New 2L Notes)
Long-term Debt, Excluding Current Maturities [Abstract]
Secured Debt		0	242.2
Debt instrument, face amount		0	321.9
Extinguishment of Debt, Amount	$ 321.9
2017 Replacement Term Loan
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net		0	0
Secured Debt		0	1,222.1
Debt instrument, face amount		0	1,374.1	1,392.9
2018 Replacement Term Loan
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net		0	0
Secured Debt		0	326.9
Debt instrument, face amount		0	364.8	369.7
Eleven Point Five Percent First Lien Senior Secured Notes
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net		0	20.8
Secured Debt		0	650
Debt instrument, face amount		0	650
Extinguishment of Debt, Amount	650
Ten Point Zero Percent Second Lien Notes due 2029
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net		0	0
Secured Debt		0	175.5
Debt instrument, face amount		0	328.3
Extinguishment of Debt, Amount	328.3
Ten Point Zero Percent Second Lien Notes (Existing Notes)
Long-term Debt, Excluding Current Maturities [Abstract]
Debt instrument, face amount				322.9
First-Out Takeback Term Loan Due November 2028
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net		0	0
Secured Debt		243.4	0
Debt instrument, face amount	229.4	228.8	0
Second-Out Takeback Term Loan Due November 2028
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net		0	0
Secured Debt		685.5	0
Debt instrument, face amount	642	640.4	0
Fourteen Point Seven Five Percent Second-Out Takeback Notes
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net		0	0
Secured Debt		836.4	0
Debt instrument, face amount	778.6	778.6	0
Receivables Financing Facility
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net		2.9	0
Secured Debt		0	0
Debt instrument, face amount		0	0	200
Ten Point Zero Percent First Lien Notes Due April 2025
Long-term Debt, Excluding Current Maturities [Abstract]
Debt instrument, face amount				$ 495
Extinguishment of Debt, Amount	$ 495
Secured Debt | Ten Point Zero Percent First Lien Notes [Member]
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net		0	0
Secured Debt | Ten Point Zero Percent Second Lien Notes (New 2L Notes)
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net		$ 0	$ 0

Debt (Schedule of Maturities of

Debt (Schedule of Maturities of Long-term Debt) (Details) $ in Millions	Dec. 29, 2023 USD ($)
Debt Disclosure [Abstract]
Fiscal 2022	$ 6.5
Fiscal 2023	8.7
Fiscal 2024	8.7
Fiscal 2025	10.9
Fiscal 2024	$ 1,613

Debt Schedule of Outstanding Bo

Debt Schedule of Outstanding Borrowings and Applicable Rates (Details) - USD ($) $ in Millions	Oct. 12, 2020	Dec. 29, 2023	Dec. 30, 2022
Debt Instrument [Line Items]
Debt, Long-term and Short-term, Combined Amount		$ 1,765.3	$ 3,092.6
Fixed-rate instruments
Debt Instrument [Line Items]
Long-term Debt, Weighted Average Interest Rate, at Point in Time		14.80%
2017 Replacement Term Loan
Debt Instrument [Line Items]
Secured Debt		$ 0	1,222.1
2018 Replacement Term Loan
Debt Instrument [Line Items]
Secured Debt		$ 0	326.9
First-Out Takeback Term Loan Due November 2028
Debt Instrument [Line Items]
Long-term Debt, Weighted Average Interest Rate, at Point in Time		11.40%
Secured Debt		$ 243.4	0
Second-Out Takeback Term Loan Due November 2028
Debt Instrument [Line Items]
Long-term Debt, Weighted Average Interest Rate, at Point in Time		13.40%
Secured Debt		$ 685.5	$ 0
Secured Debt
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Increase (Decrease)	200%
Term Loans due Sept 2024 and Feb 2025 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Increase (Decrease)	250%

Retirement Plans Narrative (Det

Retirement Plans Narrative (Details) $ in Millions	12 Months Ended
	Dec. 29, 2023 USD ($) contract	Dec. 30, 2022 USD ($) contract
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Number of Life Insurance Contract Held in Rabbi Trust | contract	48	55
Deferred Compensation Plan Assets	$ 38	$ 39.5
Deferred Compensation Plan Assets, Death Benefit on Insurance Contracts	74.2	81
Deferred Compensation Plan Assets, Loans Outstanding Against Insurance Contracts	18.3	21.6
Deferred Compensation Plan Assets, Collateral For Plan Benefits	$ 7.3
Defined Benefit Plan, Percentage of Projected Benefit Obligation	31.40%
Minimum
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate	5.40%
Maximum
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate	5.60%
Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Benefit Obligation	$ 18.9	18.7
Postretirement Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Benefit Obligation	25.9	$ 26.8
Moody's, Aa1 Rating [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Lower Threshold for Discount Rate Basis, Corporate Bonds	$ 250

Retirement Plans (Defined Contr

Retirement Plans (Defined Contribution Plan) (Details) $ in Millions	1 Months Ended	6 Months Ended		11 Months Ended	12 Months Ended
	Dec. 29, 2023 USD ($)	Dec. 30, 2022 USD ($)	Jun. 16, 2022 USD ($)	Nov. 14, 2023 USD ($)	Dec. 29, 2023 USD ($) contract	Dec. 30, 2022 USD ($) contract	Dec. 31, 2021 USD ($)
Defined Contribution Plan Disclosure [Line Items]
Number of Life Insurance Contract Held in Rabbi Trust | contract					48	55
Deferred Compensation Plan Assets, Collateral For Plan Benefits	$ 7.3				$ 7.3
Foreign Plan
Defined Contribution Plan Disclosure [Line Items]
Deferred Compensation Plan Assets, Collateral For Plan Benefits		$ 7.3				$ 7.3
Defined Contribution Plan, 401 K [Member]
Defined Contribution Plan Disclosure [Line Items]
Employer matching contribution, percent of match					50%
Defined Contribution Plan, Cost	$ 2.5	$ 7.8	$ 9.6	$ 18.6			$ 22.2

Equity (Details)

Equity (Details) - USD ($) $ / shares in Units, $ in Millions	6 Months Ended		11 Months Ended	12 Months Ended
	Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 29, 2023	Dec. 31, 2021	Sep. 29, 2022	Mar. 01, 2017
Class of Stock [Line Items]
Preferred shares, shares authorized (in shares)	500,000,000
Preferred shares, par value (in usd per share)	$ 0.01
Preferred shares, shares issued (in shares)	0
Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture			$ (0.1)		$ 0.1
Treasury Stock, Common
Class of Stock [Line Items]
Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture			(0.1)	$ 0	0
September 2022 Share Repurchase Program
Class of Stock [Line Items]
Stock Repurchase Program, Number of Shares Authorized to be Repurchased						1,317,093
March 2017 Repurchase Program [Member]
Class of Stock [Line Items]
Stock Repurchase Program, Authorized Amount							$ 1,000
Repurchase of ordinary shares, value	$ 0	$ 0	$ 0		$ 0

Share Plans (Narrative) (Detail

Share Plans (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	6 Months Ended		11 Months Ended	12 Months Ended
	Dec. 29, 2023	Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 29, 2023	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation cost	$ 0	$ 1.4	$ 1.7	$ 8.9		$ 10.2
Tax benefit from share-based compensation cost	$ 0	$ 0	$ 0	0		$ 0
Shares authorized under 2013 Plan			1,800,000
Share-based Compensation Arrangements by Share-based Payment Award, Equity Instruments Other than Options, Granted in Period, Fair value				$ 2.5
Share Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award Vesting Period					4 years
Expiration period					10 years
Restricted Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance Shares Award, Performance Period					3 years
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant date fair value, granted restricted share units		$ 8.34		$ 10.13
Performance Shares | Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant date fair value, granted restricted share units				$ 10.13
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of ordinary shares to be awarded					0%
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of ordinary shares to be awarded					200%

Share Plans (Schedule of Share

Share Plans (Schedule of Share Option Award Status Upon Completion of the Conversion) (Details) - $ / shares	Dec. 30, 2022	Jun. 16, 2022	Dec. 31, 2021	Dec. 25, 2020
Share-Based Payment Arrangement [Abstract]
Share options outstanding	890,485	0	5,553,519	6,069,712
Weighted-average exercise price, outstanding share options	$ 12.03	$ 0	$ 35.05	$ 35.95

Share Plans (Schedule of the Va

Share Plans (Schedule of the Valuation Assumptions Used in the Conversion) (Details) - shares	Dec. 30, 2022	Jun. 16, 2022	Dec. 31, 2021	Dec. 25, 2020
Weighted Average Assumptions
Share options outstanding	890,485	0	5,553,519	6,069,712

Share Plans (Schedule of Shar_2

Share Plans (Schedule of Share Option Activity) (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	6 Months Ended		11 Months Ended	12 Months Ended
	Dec. 29, 2023	Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Benefit from income taxes	$ (8)	$ (52)	$ (497.3)	$ (277.8)	$ (106.3)
Share Option Activity [Roll Forward]
Beginning balance		0	5,553,519	890,485	6,069,712
Expired/Forfeited			(5,553,519)		(516,193)
Ending balance		890,485	0		5,553,519
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]
Weighted-average exercise price, expired and forfeited share options			$ 35.05		$ 45.63

Share Plans (Schedule of Restri

Share Plans (Schedule of Restricted Share Unit Activity) (Details) - $ / shares	6 Months Ended		11 Months Ended	12 Months Ended
	Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 29, 2023	Dec. 31, 2021	Dec. 25, 2020
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Share options outstanding	890,485	0			5,553,519	6,069,712
Weighted-average exercise price, outstanding share options	$ 12.03	$ 0			$ 35.05	$ 35.95
Restricted Share Units
Restricted Share Unit Activity [Roll Forward]
Beginning balance		242,897			490,671
Granted	890,485		2,089,814
Exercised			(332,604)		(186,930)
Expired/Forfeited		(242,897)	(2,647,695)		(60,844)
Ending balance			0		242,897
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted-average grant date fair value, restricted share units			$ 0		$ 19.40	$ 20.96
Weighted-average grant date fair value, granted			1.18
Weighted-average grant date fair value, vested restricted share units			12.89		23.43
Weighted-average grant date fair value, forfeited restricted share units	$ 12.03	$ 19.40	$ 3.35		$ 19.58
Performance Shares Award, Performance Period				3 years

Share Plans (Schedule of Perfor

Share Plans (Schedule of Performance Share Unit Activity) (Details) - USD ($) $ / shares in Units, $ in Millions		6 Months Ended		11 Months Ended	12 Months Ended
		Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 29, 2023
Performance Shares
Performance Share Unit Activity [Roll Forward]
Beginning balance		0
Granted	[1]	675,821		1,459,493
Expired/Forfeited	[1]			(2,135,314)
Ending balance			0	0	675,821
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted-average grant date fair value, restricted share units			$ 0	$ 0	$ 8.34
Weighted-average grant date fair value, granted restricted share units		$ 8.34		10.13
Weighted-average grant date fair value, forfeited restricted share units				10.36
Performance Shares | Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted-average grant date fair value, granted restricted share units				$ 10.13
Deferred Compensation Arrangement with Individual, Compensation Expense		$ 0.1		$ 2.6
Phantom Share Units (PSUs)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Performance Shares Award, Performance Period					3 years
[1]The number of shares disclosed within this table are at the target number of 100.0%.

Share Plans (Schedule of Fair V

Share Plans (Schedule of Fair Value Assumptions for Performance Share Unit) (Details) - Performance Shares	6 Months Ended	11 Months Ended
	Dec. 30, 2022	Nov. 14, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected share price volatility	38.90%	40.10%
Peer group stock price volatility	128%	124.70%
Correlation of returns	24.40%	23.80%

Guarantees (Narrative) (Details

Guarantees (Narrative) (Details) - USD ($) $ in Millions	Dec. 29, 2023	Dec. 30, 2022
Others
Guarantor Obligations [Line Items]
Maximum future payments	$ 31.4
Asset Pledged as Collateral [Member]
Guarantor Obligations [Line Items]
Restricted Cash	42.9
Mallinckrodt Baker | Indemnification Agreement
Guarantor Obligations [Line Items]
Escrow	30
Mallinckrodt Baker | Indemnification Agreement | Other Assets
Guarantor Obligations [Line Items]
Escrow	$ 20.2	$ 19.3

Commitments and Contingencies (

Commitments and Contingencies (Narrative) (Details)

May 01, 2007 Defendent

Dec. 29, 2023 USD ($)

Nov. 21, 2023 USD ($)

Nov. 14, 2023 USD ($)

Aug. 24, 2023 USD ($)

Aug. 23, 2023 USD ($)

Jun. 16, 2023 USD ($)

Dec. 30, 2022 USD ($)

Sep. 09, 2022 USD ($)

Jun. 16, 2022 USD ($)

Sep. 28, 2021 USD ($)

Aug. 07, 2018 USD ($)

Mar. 04, 2016 USD ($)

Apr. 11, 2014 USD ($)

Loss Contingencies [Line Items]

Environmental liabilities

$ 36,100,000

Environmental liabilities, current

1,000,000

Environmental liabilities

35,100,000

$ 35,800,000

Debt instrument, face amount

$ 1,647,800,000

3,534,100,000

Reorganization Items. Makewhole Claim, 2025 First Lien Senior Secured Notes

$ 14,900,000

Opioid-Related Litigation Settlement, Payment Year One

$ 200,000,000

Opioid-Related Litigation Settlement, Final Payment

$ 250,000,000

2023 Restructuring Support Agreement, Trust Contingent Value Rights, Share Percentage of Reorganized New Company

5%

Environmental Loss Contingency, Statement of Financial Position [Extensible Enumeration]

Environmental liabilities

Environmental Loss Contingency, Current, Statement of Financial Position [Extensible Enumeration]

Accrued and other current liabilities

Ten Point Zero Percent First Lien Notes Due April 2025

Loss Contingencies [Line Items]

Debt instrument, face amount

$ 495,000,000

Lower Passaic River, New Jersey

Loss Contingencies [Line Items]

Loss Contingency, Settlement Agreement, Amount

$ 300,000

$ 280,600

Remedial cost, estimate

$ 1,380,000,000

$ 1,700,000,000

Upper 9 Miles, Lower Passaic River, New Jersey

Loss Contingencies [Line Items]

Remedial cost, estimate

$ 21,000,000

$ 441,000,000

Legal contingency, cost reopener

$ 3,700,000,000

Lower Passaic River, New Jersey

Loss Contingencies [Line Items]

Number of defendants | Defendent

70

StrataGraft [Member]

Loss Contingencies [Line Items]

Remedial cost, estimate

20,000,000

Minimum

Loss Contingencies [Line Items]

Remedial cost, estimate

17,700,000

Minimum | Lower Passaic River, New Jersey

Loss Contingencies [Line Items]

Remedial cost, estimate

365,000,000

Maximum

Loss Contingencies [Line Items]

Remedial cost, estimate

47,900,000

Maximum | Lower Passaic River, New Jersey

Loss Contingencies [Line Items]

Remedial cost, estimate

$ 3,200,000,000

Maximum | Medicaid Lawsuit [Member]

Loss Contingencies [Line Items]

Remedial cost, estimate

$ 640,000,000

Fair Value, Measurements, Recurring

Loss Contingencies [Line Items]

Contingent consideration

14,700,000

$ 15,000,000

7,300,000

Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3

Loss Contingencies [Line Items]

Contingent consideration

$ 14,700,000

$ 7,300,000

Financial Instruments and Fai_3

Financial Instruments and Fair Value Measurements (Narrative) (Details) $ in Millions	1 Months Ended	6 Months Ended		11 Months Ended	12 Months Ended
	Dec. 29, 2023 USD ($)	Dec. 30, 2022 USD ($)	Jun. 16, 2022 USD ($)	Nov. 14, 2023 USD ($)	Dec. 31, 2021 USD ($)	Nov. 21, 2023	Mar. 13, 2023 USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Unrealized Gain (Loss) on Investments	$ (13.5)	$ (9.2)	$ (22.2)	$ (10.1)	$ (4.7)
Restricted Cash and Investments, Current	40.8	20.6	113	47	24
Restricted Cash and Investments, Noncurrent	39.9	36.6	$ 36.4	39.7	$ 36.2
Derivative, Notional Amount							$ 860
Derivative, Interest Rate Cap, Premium				20
Unrealized Gain (Loss) on Interest Rate Cash Flow Hedges, Pretax, Accumulated Other Comprehensive Income (Loss)				5.7
Other Comprehensive Income (Loss), Net Investment Hedge, Gain (Loss), Reclassification, before Tax				0.7
Unrealized Gain (Loss) on Derivatives	8.4
London Interbank Offered Rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative, Cap Interest Rate							4.65%
Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative, Cap Interest Rate							3.84%
Professional Fees Escrow Account
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Restricted cash	17.6			$ 24
Takeback Term Loans | Derivative Financial Instruments, Liabilities | Scenario 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative, Remaining Maturity				5 years
Takeback Term Loans | Derivative Financial Instruments, Liabilities | Scenario 1 | Measurement Input Probability
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative, Remaining Maturity | pURE						0.2500
Takeback Term Loans | Derivative Financial Instruments, Liabilities | Scenario 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative, Remaining Maturity				5 years
Takeback Term Loans | Derivative Financial Instruments, Liabilities | Scenario 2 | Measurement Input Probability
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative, Remaining Maturity | pURE						0.2500
Takeback Term Loans | Derivative Financial Instruments, Liabilities | Scenario 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative, Remaining Maturity				5 years
Takeback Term Loans | Derivative Financial Instruments, Liabilities | Scenario 3 | Measurement Input Probability
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative, Remaining Maturity | pURE						0.0625
Fourteen Point Seven Five Percent Second-Out Takeback Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Stated interest rate				14.75%
Fourteen Point Seven Five Percent Second-Out Takeback Notes | Derivative Financial Instruments, Liabilities | Scenario 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative, Remaining Maturity				5 years
Fourteen Point Seven Five Percent Second-Out Takeback Notes | Derivative Financial Instruments, Liabilities | Scenario 1 | Measurement Input Probability
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative, Remaining Maturity | pURE						0.2500
Fourteen Point Seven Five Percent Second-Out Takeback Notes | Derivative Financial Instruments, Liabilities | Scenario 1 | Measurement Input Coupon Rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative, Remaining Maturity | pURE						0.1475
Fourteen Point Seven Five Percent Second-Out Takeback Notes | Derivative Financial Instruments, Liabilities | Scenario 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative, Remaining Maturity				5 years
Fourteen Point Seven Five Percent Second-Out Takeback Notes | Derivative Financial Instruments, Liabilities | Scenario 2 | Measurement Input Probability
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative, Remaining Maturity | pURE						0.2500
Fourteen Point Seven Five Percent Second-Out Takeback Notes | Derivative Financial Instruments, Liabilities | Scenario 2 | Measurement Input Coupon Rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative, Remaining Maturity | pURE						0.1475
Fourteen Point Seven Five Percent Second-Out Takeback Notes | Derivative Financial Instruments, Liabilities | Scenario 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative, Remaining Maturity				5 years
Fourteen Point Seven Five Percent Second-Out Takeback Notes | Derivative Financial Instruments, Liabilities | Scenario 3 | Measurement Input Probability
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative, Remaining Maturity | pURE						0.0625
Fourteen Point Seven Five Percent Second-Out Takeback Notes | Derivative Financial Instruments, Liabilities | Scenario 3 | Measurement Input Coupon Rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative, Remaining Maturity | pURE						0.1475
Senior Notes | Five Point Five Percent Notes [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Stated interest rate			5.50%
Senior Notes | Five Point Six Two Five Percent Note
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Stated interest rate			5.625%
Carrying Value | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Restricted cash	80.7	57.2
Carrying Value | Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash surrender value of life insurance	45.3	46.7
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of contingent consideration upon acquisition	14.7	7.3		$ 15
Debt and equity securities held in rabbi trusts	43.3	36.6
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of contingent consideration upon acquisition	0	0
Debt and equity securities held in rabbi trusts	29.1	24.8
Fair Value, Measurements, Recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of contingent consideration upon acquisition	0	0
Debt and equity securities held in rabbi trusts	14.2	11.8
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of contingent consideration upon acquisition	14.7	7.3
Debt and equity securities held in rabbi trusts	$ 0	$ 0

(Schedule of Fair Value of Asse

(Schedule of Fair Value of Assets and Liabilities Measured at Fair Value on a Recurring Basis) (Details) - USD ($) $ in Millions	Dec. 29, 2023	Nov. 14, 2023	Dec. 30, 2022
Assets:
Derivative Liability, Statement of Financial Position [Extensible Enumeration]	Accrued and other current liabilities
Derivative Liability, Current, Statement of Financial Position [Extensible Enumeration]	Accrued and other current liabilities
Derivative Liability		$ 15.1
Liabilities:
Cash Flow Hedge Derivative Instrument Assets at Fair Value	$ 12.9
Fair Value, Measurements, Recurring
Assets:
Debt and equity securities held in rabbi trusts	43.3		$ 36.6
Other Assets, Fair Value Disclosure	28.9		25.5
Total assets at fair value	85.1		62.1
Derivative Liability	15.1
Liabilities:
Deferred compensation liabilities	21		26
Contingent consideration	14.7	$ 15	7.3
Total liabilities at fair value	50.8		33.3
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets:
Debt and equity securities held in rabbi trusts	29.1		24.8
Other Assets, Fair Value Disclosure	28.9		25.5
Total assets at fair value	58		50.3
Derivative Liability	0
Liabilities:
Deferred compensation liabilities	0		0
Contingent consideration	0		0
Total liabilities at fair value	0		0
Cash Flow Hedge Derivative Instrument Assets at Fair Value	0
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2)
Assets:
Debt and equity securities held in rabbi trusts	14.2		11.8
Other Assets, Fair Value Disclosure	0		0
Total assets at fair value	14.2		11.8
Derivative Liability	0
Liabilities:
Deferred compensation liabilities	21		26
Contingent consideration	0		0
Total liabilities at fair value	21		26
Cash Flow Hedge Derivative Instrument Assets at Fair Value	0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3)
Assets:
Debt and equity securities held in rabbi trusts	0		0
Other Assets, Fair Value Disclosure	0		0
Total assets at fair value	12.9		0
Derivative Liability	15.1
Liabilities:
Deferred compensation liabilities	0		0
Contingent consideration	14.7		7.3
Total liabilities at fair value	29.8		$ 7.3
Cash Flow Hedge Derivative Instrument Assets at Fair Value	$ 12.9

(Schedule of Reconciliation of

(Schedule of Reconciliation of Changes in Fair Value of Contingent Consideration) (Details) - USD ($) $ in Millions	1 Months Ended	11 Months Ended
	Dec. 29, 2023	Nov. 14, 2023	Dec. 30, 2022	Jun. 16, 2022
Reorganization, Chapter 11, Plan Effect Adjustment
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Contingent consideration				$ (41.8)
Fair Value, Measurements, Recurring
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Contingent consideration	$ 14.7	$ 15	$ 7.3
Fair Value, Inputs, Level 3 | Fair Value, Measurements, Recurring
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Contingent consideration	14.7		$ 7.3
Fair Value, Inputs, Level 3 | Fair Value, Measurements, Recurring | Contingent Liabilities [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	15	7.3
Ending balance	14.7	15
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Period Increase (Decrease)	$ (0.3)	(7.2)
Fair Value, Inputs, Level 3 | Fair Value, Measurements, Recurring | Contingent Liabilities [Member] | Reorganization, Chapter 11, Fresh-Start Adjustment
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fresh-Start Adjustment, Terlivaz CVR		14.9
StrataGraft CVR | Reorganization, Chapter 11, Plan Effect Adjustment
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Contingent Liability		$ 14.9		$ 6.8

(Schedule of Carrying Amount an

(Schedule of Carrying Amount and Fair Value of Long-term Debt) (Details) - USD ($) $ in Millions	Dec. 29, 2023	Nov. 14, 2023	Dec. 30, 2022	Jun. 16, 2022
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long term debt	$ 1,731.2		$ 2,684.6
Long-term Debt, Current Maturities	6.5		44.1
Long-term Debt, Gross	1,758.8		3,048.5
Debt, Long-term and Short-term, Combined Amount	1,765.3		3,092.6
Ten Point Zero Percent First Lien Notes [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Secured Debt	0		475.9
Ten Point Zero Percent Second Lien Notes (New 2L Notes)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Secured Debt	0		242.2
Eleven Point Five Percent First Lien Senior Secured Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Secured Debt	0		650
Ten Point Zero Percent Second Lien Notes due 2029
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Secured Debt	0		175.5
2017 Replacement Term Loan
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Secured Debt	0		1,222.1
2018 Replacement Term Loan
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Secured Debt	0		326.9
Fourteen Point Seven Five Percent Second-Out Takeback Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Secured Debt	836.4		0
Stated interest rate		14.75%
First-Out Takeback Term Loan Due November 2028
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Secured Debt	243.4		0
Second-Out Takeback Term Loan Due November 2028
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Secured Debt	685.5		0
Senior Notes | Five Point Five Percent Notes [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Stated interest rate				5.50%
Senior Notes | Five Point Six Two Five Percent Note
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Stated interest rate				5.625%
Senior Notes | Ten Point Zero Percent Second Lien Notes (New 2L Notes)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Stated interest rate				10%
Fair Value, Inputs, Level 1 [Member] | Ten Point Zero Percent First Lien Notes [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long term debt	0		425.9
Fair Value, Inputs, Level 1 [Member] | Ten Point Zero Percent Second Lien Notes (New 2L Notes)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long term debt	0		216.8
Fair Value, Inputs, Level 1 [Member] | Eleven Point Five Percent First Lien Senior Secured Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long term debt	0		552.6
Fair Value, Inputs, Level 1 [Member] | Ten Point Zero Percent Second Lien Notes due 2029
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long term debt	0		176.7
Fair Value, Inputs, Level 1 [Member] | Fourteen Point Seven Five Percent Second-Out Takeback Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long term debt	844.4		0
Level 2 | 2017 Replacement Term Loan
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long term debt	0		1,037.8
Level 2 | 2018 Replacement Term Loan
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long term debt	0		274.8
Level 2 | First-Out Takeback Term Loan Due November 2028
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long term debt	232.8		0
Level 2 | Second-Out Takeback Term Loan Due November 2028
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long term debt	$ 654		$ 0

(Schedules of Concentration of

(Schedules of Concentration of Risk) (Details)	1 Months Ended	6 Months Ended		11 Months Ended	12 Months Ended
	Dec. 29, 2023	Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 29, 2023	Dec. 30, 2022	Dec. 31, 2021
Distributor Concentration Risk | Revenue from Contract with Customer Benchmark [Member] | CuraScript, Inc [Member]
Concentration Risk [Line Items]
Concentration risk, percentage			15.60%				26.10%
Distributor Concentration Risk | Revenue from Contract with Customer Benchmark [Member] | McKesson Corporation [Member]
Concentration Risk [Line Items]
Concentration risk, percentage	10.80%
Distributor Concentration Risk | Revenue from Contract with Customer Benchmark [Member] | Amerisource Bergen Corporation [Member]
Concentration Risk [Line Items]
Concentration risk, percentage		10%
Distributor Concentration Risk | Revenue from Contract with Customer Benchmark [Member] | FFF Enterprises, Inc.
Concentration Risk [Line Items]
Concentration risk, percentage	23.10%	26.10%	11.80%	22.30%
Distributor Concentration Risk | Accounts Receivable Attributable to Distributors | McKesson Corporation [Member]
Concentration Risk [Line Items]
Concentration risk, percentage					20%	17.30%
Distributor Concentration Risk | Accounts Receivable Attributable to Distributors | Amerisource Bergen Corporation [Member]
Concentration Risk [Line Items]
Concentration risk, percentage					24.20%	23.30%
Distributor Concentration Risk | Accounts Receivable Attributable to Distributors | FFF Enterprises, Inc.
Concentration Risk [Line Items]
Concentration risk, percentage						16.20%
Product Concentration Risk | Net Sales Attributable to Products | Acthar Gel
Concentration Risk [Line Items]
Concentration risk, percentage	23.50%	28.30%	25.40%	22.70%			26.90%
Product Concentration Risk | Net Sales Attributable to Products | Inomax
Concentration Risk [Line Items]
Concentration risk, percentage	14.50%	16.70%	19%	16.50%			20.30%
Product Concentration Risk | Net Sales Attributable to Products | Therakos
Concentration Risk [Line Items]
Concentration risk, percentage	16.10%	12.50%	12.50%	13.60%			12.10%
Product Concentration Risk | Net Sales Attributable to Products | APAP
Concentration Risk [Line Items]
Concentration risk, percentage	13.40%	10.70%	11%	11.40%

Segment and Geographical Data_2

Segment and Geographical Data (Schedule of Segment Reporting Information by Business Segment) (Details) - USD ($) $ in Millions	1 Months Ended	6 Months Ended		11 Months Ended	12 Months Ended
	Dec. 29, 2023	Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 31, 2021
Segment Reporting Information [Line Items]
Net sales	$ 243	$ 1,039.7	$ 874.6	$ 1,622.9	$ 2,208.8
Operating income (loss)	(20.2)	(316.7)	(57.8)	(517.4)	(202.9)
Intangible asset amortization	(16.2)	(318.7)	(281.8)	(449.6)	(581.1)
Restructuring and related charges, net	0	(11.1)	(9.6)	(0.9)	(26.9)
Other Asset Impairment Charges, Gross	(3.8)	0	0	(179.9)	(154.9)
Other Asset Impairment Charges	2.6	0	0	135.9	154.9
Opioid-Related Litigation Settlement loss	0	0	0	0	125
Depreciation and amortization	25.8	347.5	321.8	490.3	675.8
Restructuring and related costs, accelerated depreciation	0	1	0	0.8	2.1
Employee Benefits and Share-based Compensation	0	(1.4)	(1.7)	(8.9)	(10.2)
Assets	3,733.6	6,013.8
Inventory provisions				44
StrataGraft [Member]
Segment Reporting Information [Line Items]
Other Asset Impairment Charges, Gross	3.8
Petition Amount Filed with Bankruptcy Court
Segment Reporting Information [Line Items]
Bad Debt Expense, Customer Bankruptcy, Pre-Petition Amount	0	(6.4)	0	0	0
Specialty Brands [Member]
Segment Reporting Information [Line Items]
Other Asset Impairment Charges					154.9
Specialty Brands [Member] | StrataGraft [Member]
Segment Reporting Information [Line Items]
Other Asset Impairment Charges				50.1
Specialty Generics [Member]
Segment Reporting Information [Line Items]
Other Asset Impairment Charges				85.8
Operating Segments
Segment Reporting Information [Line Items]
Operating income (loss)	14.8	110.2	332.5	366.1	920.7
Operating Segments | Specialty Brands [Member]
Segment Reporting Information [Line Items]
Net sales	139.8	682.4	587.1	949.2	1,547
Operating income (loss)	9	113.8	267.2	209.9	812.8
Depreciation and amortization	15.3	323.6	288.4	455.3	597.7
Operating Segments | Specialty Generics [Member]
Segment Reporting Information [Line Items]
Net sales	103.2	357.3	287.5	673.7	661.8
Operating income (loss)	5.8	(3.6)	65.3	156.2	107.9
Depreciation and amortization	10.5	23.9	33.4	35	78.1
Corporate, Non-Segment
Segment Reporting Information [Line Items]
Corporate and allocated expenses	(4)	(39.3)	(48.2)	(45.8)	(129.6)	[1]
Intangible asset amortization	(25.8)	(347.5)	(321.8)	(490.3)	(675.8)
Separation costs	1.4	21.2	9	157.7	1.2	[2]
Opioid-Related Litigation Settlement loss	$ 0	$ 0	$ 0	$ 0	$ (125)
[1] Includes administration expenses and certain compensation, legal, environmental and other costs not charged to the Company's reportable segments. (3) Includes $135.9 million and $154.9 million of impairment charges on intangible assets during the period December 31, 2022 through November 14, 2023 (Predecessor) and fiscal 2021 (Predecessor), respectively, as further described in Note 12, a $44.0 million Acthar Gel inventory write-down to net realizable value during the period December 31, 2022 through November 14, 2023 (Predecessor), and $3.8 million of impairment charges on StrataGraft long-lived assets during the period November 15, 2023 through December 29, 2023 (Successor). Represents costs primarily related to professional fees incurred by the Company (including where the Company is responsible for the fees of third parties) in connection with its evaluation of its financial situation and related discussions with its stakeholders prior to the commencement of the 2023 Bankruptcy Proceedings, expenses incurred related to the severance of certain former executives of the Predecessor as a result of the 2020 Bankruptcy Proceedings, in addition to professional fees and costs incurred as the Company explores potential sales of non-core assets to enable further deleveraging post-emergence. As of the 2023 Petition Date and 2020 Petition Date, professional fees directly related to the 2023 Bankruptcy Proceedings and 2020 Bankruptcy Proceedings, respectively, that were previously reflected as liabilities management and separation costs were classified on a go-forward basis as reorganization items, net until the 2023 Effective Date and the 2020 Effective Date, respectively.

Segment and Geographical Data_3

Segment and Geographical Data (Schedule of Net Sales from External Costumers by Product) (Details) - USD ($) $ in Millions		1 Months Ended	6 Months Ended		11 Months Ended	12 Months Ended
		Dec. 29, 2023	Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 31, 2021
Segment Reporting Information [Line Items]
Net sales		$ 243	$ 1,039.7	$ 874.6	$ 1,622.9	$ 2,208.8
Operating Segments | Specialty Brands [Member]
Segment Reporting Information [Line Items]
Net sales		139.8	682.4	587.1	949.2	1,547
Operating Segments | Specialty Generics [Member]
Segment Reporting Information [Line Items]
Net sales		103.2	357.3	287.5	673.7	661.8
Acthar Gel | Operating Segments | Specialty Brands [Member]
Segment Reporting Information [Line Items]
Net sales		57	294.1	221.9	368.3	593.6
Inomax | Operating Segments | Specialty Brands [Member]
Segment Reporting Information [Line Items]
Net sales		35.3	173.9	165.8	267.9	448.5
Therakos | Operating Segments | Specialty Brands [Member]
Segment Reporting Information [Line Items]
Net sales		39.1	130.5	109.6	220	266.5
Amitiza | Operating Segments | Specialty Brands [Member]
Segment Reporting Information [Line Items]
Net sales	[1]	5	77.1	81.5	72	196.9
Other Products | Operating Segments | Specialty Brands [Member]
Segment Reporting Information [Line Items]
Net sales		1.1	5.6	8.3	7.7	41.5
Opioids | Specialty Generics [Member]
Segment Reporting Information [Line Items]
Net sales		31.6	117.9	88.8	230.7	213.2
ADHD | Specialty Generics [Member]
Segment Reporting Information [Line Items]
Net sales		13.5	28.4	17.5	101.4	37.4
Addiction Treatment | Specialty Generics [Member]
Segment Reporting Information [Line Items]
Net sales		10.5	35	30	55.6	68.3
Other Generics | Specialty Generics [Member]
Segment Reporting Information [Line Items]
Net sales		1.6	6.8	4.9	8.2	12
Generics | Specialty Generics [Member]
Segment Reporting Information [Line Items]
Net sales		57.2	188.1	141.2	395.9	330.9
Controlled substances | Specialty Generics [Member]
Segment Reporting Information [Line Items]
Net sales		11.6	47	37.6	75.5	93.4
APAP | Specialty Generics [Member]
Segment Reporting Information [Line Items]
Net sales		32.5	111.4	96.5	184.8	215.9
Other API | Specialty Generics [Member]
Segment Reporting Information [Line Items]
Net sales		1.9	10.8	12.2	17.5	21.6
API | Specialty Generics [Member]
Segment Reporting Information [Line Items]
Net sales		46	169.2	146.3	277.8	330.9
Terlivaz | Operating Segments | Specialty Brands [Member]
Segment Reporting Information [Line Items]
Net sales		$ 2.3	$ 1.2	$ 0	$ 13.3	$ 0
[1] Amitiza net sales consist of both product and royalty net sales.

Segment and Geographical Data_4

Segment and Geographical Data (Schedule of Net Sales and Long-Lived Assets by Geographic Area) (Details) - USD ($) $ in Millions	1 Months Ended	6 Months Ended		11 Months Ended	12 Months Ended
	Dec. 29, 2023	Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 31, 2021
Schedule of Net Sales and Long-Lived Assets by Geographic Area [Line Items]
Net sales	$ 243	$ 1,039.7	$ 874.6	$ 1,622.9	$ 2,208.8
Long-Lived Assets	333.3	468.4
United States
Schedule of Net Sales and Long-Lived Assets by Geographic Area [Line Items]
Net sales	212.8	928.3	784.2	1,448.9	1,991.8	[1]
Long-Lived Assets	165.9	287.3
EMEA
Schedule of Net Sales and Long-Lived Assets by Geographic Area [Line Items]
Net sales	28.8	100.4	73.6	157.1	181.8	[1]
Long-Lived Assets	164.6	178
Other Countries
Schedule of Net Sales and Long-Lived Assets by Geographic Area [Line Items]
Net sales	1.4	11	$ 16.8	$ 16.9	$ 35.2	[1]
Other Address
Schedule of Net Sales and Long-Lived Assets by Geographic Area [Line Items]
Long-Lived Assets	2.8	3.1
IRELAND
Schedule of Net Sales and Long-Lived Assets by Geographic Area [Line Items]
Long-Lived Assets	$ 162.1	$ 174.9
[1] Net sales are attributed to regions based on the location of the entity that records the transaction, none of which relate to the country of Ireland.

Subsequent Events (Details)

Subsequent Events (Details) - shares	Feb. 02, 2024	Jun. 16, 2022
Subsequent Event [Line Items]
Shares authorized under 2013 Plan		1,800,000
Subsequent Event [Member]
Subsequent Event [Line Items]
Shares authorized under 2013 Plan	1,036,649

Schedule II - Valuation and Q_2

Schedule II - Valuation and Qualifying Accounts (Details) - USD ($) $ in Millions	1 Months Ended	6 Months Ended		11 Months Ended	12 Months Ended
	Dec. 29, 2023	Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 31, 2021
Allowance for doubtful accounts
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	$ 5.6	$ 5.9	$ 4.7	$ 4.4	$ 4.5
Charged to Costs and Expenses	2.9	0.5	1.2	4.2	1.2
Charged to Other Accounts	0	0	0	0	0
Deductions	(2)	(2)	0	(3)	(1)
Balance at End of Period	6.5	4.4	5.9	5.6	4.7
Sales Returns and Allowances
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	250.5	276.9	272.8	294	235.4
Charged to Costs and Expenses	182.9	848.1	715.7	1,422	2,166
Charged to Other Accounts	0	0	0	0	0
Deductions	(206)	(831)	(711.6)	(1,465.5)	(2,128.6)
Balance at End of Period	227.4	294	276.9	250.5	272.8
Tax valuation allowance
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	4,584.8	5,129.7	6,344.2	4,992.9	6,110.8
Charged to Costs and Expenses	(1.1)	(136)	(1,213.5)	(407.4)	233.4
Charged to Other Accounts	0.1	(0.8)	(1)	(0.7)	0
Deductions	0	0	0	0	0
Balance at End of Period	$ 4,583.8	$ 4,992.9	$ 5,129.7	$ 4,584.8	$ 6,344.2

Uncategorized Items - mnk-20231

Label	Element	Value
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents	us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	$ 1,127,000,000
Restructuring Fiscal 2018 Plan [Member] | Continuing Operations [Member]
Restructuring Reserve	us-gaap_RestructuringReserve	$ 100,000