For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount of deferred income and obligation to transfer product and service to customer for which consideration has been received or is receivable.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Revenue - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Disaggregation of Revenue [Line Items]
Remaining performance obligations	$ 22.4	$ 10.0
Certain Customers in China [Member] \| Customer Concentration Risk [Member] \| Maximum [Member] \| Revenue Benchmark [Member] \| Customer One [Member]
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	60.60%
Certain Customers in China [Member] \| Customer Concentration Risk [Member] \| Maximum [Member] \| Revenue Benchmark [Member] \| Customer Two [Member]
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	22.50%
Certain Customers in China [Member] \| Customer Concentration Risk [Member] \| Maximum [Member] \| Accounts Receivable [Member] \| Customer One [Member]
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	39.40%
Certain Customers in China [Member] \| Customer Concentration Risk [Member] \| Maximum [Member] \| Accounts Receivable [Member] \| Customer Two [Member]
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	19.60%
Certain Customers in China [Member] \| Customer Concentration Risk [Member] \| Maximum [Member] \| Accounts Receivable [Member] \| Customer Three [Member]
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	13.00%
Australasia Regions [Member] \| Certain Customers in China [Member]
Disaggregation of Revenue [Line Items]
Revenue recognized	$ 3.8
Deferred revenue	13.6
Fuel [Member]
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	6.0
Fuel [Member] \| European Union [Member]
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	2.2
Fuel [Member] \| Australasia Regions [Member]
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	$ 3.8