Investments - Current and Non-current of Available-for-Sale Debt Securities (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Reported under the following captions in our consolidated balance sheets:
Total	$ 3,830.8	$ 3,178.6
Cash and cash equivalents
Reported under the following captions in our consolidated balance sheets:
Current available-for-sale debt securities	19.1	15.6
Current marketable investments
Reported under the following captions in our consolidated balance sheets:
Current available-for-sale debt securities	1,750.9	1,846.8
Non-current marketable investments
Reported under the following captions in our consolidated balance sheets:
Non-current marketable investments	$ 2,060.8	$ 1,316.2

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- Definition

Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479130/326-30-45-1

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Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), classified as current.

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+ References

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