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Acquisitions (Details Textual) $ / shares in Units, $ in Millions |  | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 26, 2023 USD ($) ft² $ / shares | Jun. 30, 2024 USD ($) | Mar. 31, 2024 USD ($) | Mar. 31, 2023 USD ($) | Dec. 31, 2023 USD ($)
Business Acquisition [Line Items] |  |  |  |  |
Selling, general and administrative |  |  | $ 581.5 | $ 605.0 |
Goodwill |  |  | 6,227.4 |  | $ 6,219.2
Forecast |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Payments to Acquire Businesses, Gross, Outstanding Equity Awards |  | $ 983.9 |  |  |
Reata Pharmaceuticals, Inc |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Price per share | $ / shares | $ 172.50 |  |  |  |
Consideration transferred | $ 7,193.4 |  |  |  |
Total transaction value | 6,602.9 |  |  |  |
Selling, general and administrative | 196.4 |  |  |  |
Research and development expense asset acquired | 197.0 |  |  |  |
Operating expenses | 393.4 |  |  |  |
Inventory | 1,300.0 |  | 1,259.0 |  |
Operating lease liabilities | 151.8 |  | 151.8 |  |
Operating lease assets | $ 121.2 |  | 121.2 |  |
Lease term | 16 years |  |  |  |
Operating Lease Area | ft² | 327,400 |  |  |  |
Lessee, Operating Lease, Remaining Lease Term | 15 years |  |  |  |
Fair Value Indefinite Lived Intangible Assets Discount Rate | 14.30% |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory Amortization Period | 3 years |  |  |  |
Goodwill | $ 473.5 |  | 473.5 |  |
Business Combination, Consideration Transferred, Equity Compensation Pre-acquisition Services | 590.5 |  |  |  |
Adjustment, inventory |  |  | 44.1 |  |
Reata Pharmaceuticals, Inc | Secured Debt | The Credit Facility | Line of Credit |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Long-term debt, gross | 1,000.0 |  |  |  |
Reata Pharmaceuticals, Inc | Selling, general and administrative |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Business Combination, Separately Recognized Transactions, Additional Disclosures, Acquisition Cost Expensed |  |  |  |  | $ 28.4
Reata Pharmaceuticals, Inc | Completed technology for SKYCLARYS (U.S.) |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Intangible assets: | 4,200.0 |  | 4,200.0 |  |
Reata Pharmaceuticals, Inc | In-process research and development |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Intangible assets: | 2,300.0 |  | 2,300.0 |  |
Reata Pharmaceuticals, Inc | Priority review voucher |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Intangible assets: | 100.0 |  | 100.0 |  |
Reata Pharmaceuticals, Inc | Other clinical programs |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Intangible assets: | $ 40.0 |  | $ 40.0 |  |

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