Intangible Assets - Gross Carrying Amount (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2024	Dec. 31, 2023
Gross carrying amount and accumulated amortization of acquired identifiable intangible assets
Gross Carrying Amount	$ 236,617	$ 236,041
Accumulated Amortization	(61,611)	(47,155)
Total	$ 175,006	$ 188,886
Acquired Technology
Gross carrying amount and accumulated amortization of acquired identifiable intangible assets
Weighted Average Amortization Period	14 years	14 years
Gross Carrying Amount	$ 103,144	$ 103,060
Accumulated Amortization	(25,902)	(20,204)
Total	$ 77,242	$ 82,856
Dry stack electrolyzer technology
Gross carrying amount and accumulated amortization of acquired identifiable intangible assets
Weighted Average Amortization Period	10 years	10 years
Gross Carrying Amount	$ 29,000	$ 29,000
Accumulated Amortization	(7,492)	(5,317)
Total	$ 21,508	$ 23,683
Customer relationships, trade name and other
Gross carrying amount and accumulated amortization of acquired identifiable intangible assets
Weighted Average Amortization Period	13 years	13 years
Gross Carrying Amount	$ 104,473	$ 103,981
Accumulated Amortization	(28,217)	(21,634)
Total	$ 76,256	$ 82,347