Summary of Significant Accounting Policies - Fair Value Measurements (Details) $ in Thousands, € in Millions	Sep. 30, 2024 EUR (€) item	Sep. 30, 2024 USD ($) item	Dec. 31, 2023 USD ($)
Fair Value Measurements
Number of investments for which fair value is measured on a recurring basis using Level 3 inputs | item	0	0
Recurring
Assets:
Short-term investments		$ 300,000	$ 1,000,000
Deferred costs and other assets		121,080	113,779
Total		421,080	1,113,779
Other Liabilities
Other Liabilities		109,521	38,146
Level 1 | Recurring
Assets:
Deferred costs and other assets		118,548	97,696
Total		118,548	97,696
Level 2 | Recurring
Assets:
Short-term investments		300,000	1,000,000
Deferred costs and other assets		2,532	16,083
Total		302,532	1,016,083
Other Liabilities
Other Liabilities		8,381	9,774
Level 3 | Recurring
Other Liabilities
Other Liabilities		$ 101,140	$ 28,372
Exchangeable Debt | Embedded derivative financial instruments
Fair Value Measurements
Interest rate swap agreements and foreign currency forward contracts, gross liability balance | €	€ 750.0