Intangible Assets - Gross Carrying Amount (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2025	Dec. 31, 2024
Gross carrying amount and accumulated amortization of acquired identifiable intangible assets
Gross Carrying Amount	$ 103,344	$ 103,212
Accumulated Amortization	(20,567)	(18,552)
Total	$ 82,777	$ 84,660
Acquired technology
Gross carrying amount and accumulated amortization of acquired identifiable intangible assets
Weighted Average Amortization Period	14 years	14 years
Gross Carrying Amount	$ 34,877	$ 34,872
Accumulated Amortization	(8,467)	(7,805)
Total	$ 26,410	$ 27,067
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	$ 11,351	$ 11,351
Accumulated Amortization	(765)	(383)
Total	$ 10,586	$ 10,968
Customer relationships, trade name, and other
Gross carrying amount and accumulated amortization of acquired identifiable intangible assets
Weighted Average Amortization Period	15 years	15 years
Gross Carrying Amount	$ 57,116	$ 56,989
Accumulated Amortization	(11,335)	(10,364)
Total	$ 45,781	$ 46,625