Nature of Business and Basis of Presentation (Detail) $ / shares in Units, $ in Thousands		3 Months Ended
	Jul. 16, 2021 USD ($) $ / shares	Mar. 31, 2022 USD ($) $ / shares	Mar. 31, 2021 USD ($)	Dec. 31, 2021 USD ($) $ / shares
Business Combination, Separately Recognized Transactions [Line Items]
Common stock, par value (dollars per share) | $ / shares	$ 0.0001	$ 0.0001		$ 0.0001
Net loss		$ (11,022)	$ (8,389)
Accumulated deficit		(37,182)		$ (28,117)
Cash flows used in operating activities		(29,248)	$ (9,470)
Unrestricted cash		$ 407,333		$ 445,146
Legacy Hyzon
Business Combination, Separately Recognized Transactions [Line Items]
Cash received in transaction net of redemption and transaction costs	$ 512,900
Legacy Hyzon | Common Stock Class A
Business Combination, Separately Recognized Transactions [Line Items]
Stockholders equity note, stock split, conversion ratio (in shares)	1.772