Business Combination - Additional Information (Detail)				11 Months Ended	12 Months Ended
		Jul. 16, 2021 USD ($) $ / shares shares	Oct. 22, 2020 $ / shares shares	Dec. 31, 2020 USD ($) $ / shares	Dec. 31, 2021 USD ($) $ / shares shares	Nov. 12, 2020 shares
Business Acquisition [Line Items]
Common stock, par value (in Dollars per share) | $ / shares				$ 0.0001	$ 0.0001
Common Stock, Capital Shares Reserved for Future Issuance						11,075,000
Common stock issued, value | $	[1]			$ 18,476,000
Recognize earnout liability | $					$ 188,373,000
Business combination allocated share based expense related to earnout awards | $					13,100,000
Working capital loans | $					1,500,000
Chief Executive Officer [Member]
Business Acquisition [Line Items]
Sale of stock in shares			514,500
Initial Public Offering [Member]
Business Acquisition [Line Items]
Sale of stock in shares			22,572,502
Private Placement [Member]
Business Acquisition [Line Items]
Working capital loans | $					$ 1,500,000
Sale of stock in shares			6,514,500
Sale of Stock, Price Per Share | $ / shares			$ 1.00
New Hyzon [Member]
Business Acquisition [Line Items]
Number of trading days for determining the share price					20 days
Number of consecutive trading days for determining the share price					30 days
Maximum earnout period					5 years
Maximum earnout shares issued					5,250,000
New Hyzon [Member] | Tranche One [Member]
Business Acquisition [Line Items]
Sale of stock price | $ / shares					$ 18
Number of shares issued					9,000,000
New Hyzon [Member] | Tranche Two [Member]
Business Acquisition [Line Items]
Sale of stock price | $ / shares					$ 20
Number of shares issued					9,000,000
New Hyzon [Member] | Tranche Three [Member]
Business Acquisition [Line Items]
Sale of stock price | $ / shares					$ 35
Number of shares issued					5,250,000
Ascent options [Member]
Business Acquisition [Line Items]
Business combination share based compensation by share based award exercise price per share of options excercised | $ / shares					$ 2.73
Business combination share based compensation by share based award number of shares as a result of options excercised before business combination					3,900,000
Business combination share based compensation by share based award number of shares as a result of options excercised after business combination					6,900,000
PIPE Financing [Member]
Business Acquisition [Line Items]
Debt instrument principal amount | $		$ 45,000,000
Percentage of price per share of converted shares equal to price per share paid by the pipe financing investors		90.00%
Debt instrument shares converted		5,022,052
Legacy Hyzon [Member]
Business Acquisition [Line Items]
Common stock, par value (in Dollars per share) | $ / shares		$ 0.001
Recognize earnout liability | $		$ 103,800,000			$ 188,400,000
Business Combination [Member]
Business Acquisition [Line Items]
Issue shares of Legacy Hyzon common stock					4,100,000
Common Class A [Member]
Business Acquisition [Line Items]
Issued and outstanding share		246,994,209
Common Class A [Member] | Share-based Payment Arrangement, Option [Member]
Business Acquisition [Line Items]
Common Stock, Capital Shares Reserved for Future Issuance		21.7
Common Class A [Member] | PIPE Financing [Member]
Business Acquisition [Line Items]
Issue shares of Legacy Hyzon common stock		35,500,000
Sale of stock price | $ / shares		$ 10.00
Common stock issued, value | $		$ 355,000,000
Common Class A [Member] | Legacy Hyzon [Member]
Business Acquisition [Line Items]
Common stock, par value (in Dollars per share) | $ / shares		$ 0.0001
Stockholders equity note, stock split, conversion ratio		1.772
Proceeds from issuance of common stock | $		$ 173,400,000
Common Class A [Member] | Business Combination [Member]
Business Acquisition [Line Items]
Common stock was converted into, shares of common stock of the post-combination					7,200,000

[1] Issuance of common stock, net of issuance costs of $1,024 and conversion of convertible notes have been retroactively restated to give effect to the recapitalization transaction.