Financial Instruments and Fair Value Measurements (Schedule of Reconciliation of Changes in Fair Value of Contingent Liabilities) (Details) - Level 3 - Recurring - USD ($) $ in Millions	6 Months Ended
Jun. 25, 2021	Dec. 25, 2020
Contingent Liabilities
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 34.7
Fair value adjustment	(5.5)
Ending balance	29.2
StrataGraft [Member] \| Stratatech
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value of contingent liability	29.2	$ 19.1
MNK-6105 [Member] \| Ocera [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Contingent Consideration, Liability	$ 0.0	$ 15.6

Amount of liability recognized arising from contingent consideration in a business combination.

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The amount of liability arising from an inherited contingency (as defined) which has been recognized as of the acquisition date.

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Amount of increase (decrease) of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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