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	$ 243.0	$ 1,039.7	$ 874.6	$ 1,622.9	$ 2,208.8
Cost of sales	179.1	991.0	582.0	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	0.0	11.1	9.6	0.9	26.9
Non-restructuring impairment charges	2.6	0.0	0.0	135.9	154.9
Opioid-Related Litigation Settlement loss	0.0	0.0	0.0	0.0	125.0
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	10.0	(14.6)	(6.5)	22.0
Reorganization items, net	(4.0)	(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	(8.0)	(52.0)	(497.3)	(277.8)	(106.3)
Loss from continuing operations	(38.2)	(598.3)	(314.0)	(1,631.3)	(723.5)
Income from discontinued operations, net of tax benefit of $—, $—, $—, $—, and $(5.0)	0.0	0.2	0.9	0.0	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