Fair Value Measurements - Assets and liabilities measured at fair value on a recurring basis (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Jun. 30, 2023	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Jan. 14, 2022	Dec. 31, 2020
Fair Value
Change in fair value of contingent consideration		$ 30,024	$ 16,468	$ 11,176
Payments of contingent consideration		10,105	2,667	1,541
Recurring basis | Level 1 | Cash and cash equivalents
Fair Value
Assets, Fair Value			212,577
Recurring basis | Level 1 | U.S. Treasuries
Fair Value
Assets, Fair Value			1,139,310
Recurring basis | Level 1 | Equity securities
Fair Value
Assets, Fair Value			134,836
Recurring basis | Level 2 | Corporate bonds
Fair Value
Assets, Fair Value			193,633
Recurring basis | Level 3 | Contingent consideration
Fair Value
Liabilities, Fair value		126,216	116,165
Joule Processing LLC
Fair Value
Contingent consideration		41,700			$ 130,000
Change in fair value of contingent consideration		22,300
Carrying value | Recurring basis | Contingent consideration
Fair Value
Liabilities, Fair value		126,216	116,165
Carrying value | Recurring basis | Cash and cash equivalents
Fair Value
Assets, Fair Value			212,577
Carrying value | Recurring basis | Corporate bonds
Fair Value
Assets, Fair Value			193,633
Carrying value | Recurring basis | U.S. Treasuries
Fair Value
Assets, Fair Value			1,139,310
Carrying value | Recurring basis | Equity securities
Fair Value
Assets, Fair Value			134,836
Fair value | Contingent consideration
Fair Value
Payments of contingent consideration	$ 19,000
Fair value | Recurring basis | Contingent consideration
Fair Value
Liabilities, Fair value		126,216	116,165
Fair value | Recurring basis | Cash and cash equivalents
Fair Value
Assets, Fair Value			212,577
Fair value | Recurring basis | Corporate bonds
Fair Value
Assets, Fair Value			193,633
Fair value | Recurring basis | U.S. Treasuries
Fair Value
Assets, Fair Value			1,139,310
Fair value | Recurring basis | Equity securities
Fair Value
Assets, Fair Value			134,836
Fair value | Giner ELX, Inc | Contingent consideration
Fair Value
Liabilities, Fair value		18,000	14,500
Contingent consideration		2,000				$ 16,000
Change in fair value of contingent consideration		5,500
Fair value | United Hydrogen Group Inc | Contingent consideration
Fair Value
Liabilities, Fair value		900	1,500
Contingent consideration						$ 1,100
Change in fair value of contingent consideration		600
Fair value | Applied Cryo Technologies Inc | Contingent consideration
Fair Value
Liabilities, Fair value		0	15,900
Contingent consideration		14,000
Change in fair value of contingent consideration		3,100
Fair value | Applied Cryo Technologies Inc | Contingent consideration | Maximum
Fair Value
Change in fair value of contingent consideration		19,000
Fair value | Frames Holding B.V. | Contingent consideration
Fair Value
Liabilities, Fair value		31,800	$ 31,000
Contingent consideration				$ 29,100
Change in fair value of contingent consideration		300
Foreign Currency Contracts, Liability, Fair Value Disclosure		$ 1,100