The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 912
-SubTopic 730
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6472174&loc=d3e58812-109433

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 985
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6501960&loc=d3e128462-111756

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 730
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6420194&loc=d3e21568-108373

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Commitments and Contingencies - Narrative (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Jul. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Commitments And Contingencies [Line Items]
Rental expense		$ 5,700	$ 4,600	$ 4,400
Research and development		287,167	$ 132,001	$ 63,619
Navistar, Inc. \| JDA
Commitments And Contingencies [Line Items]
Research and development		$ 10,000
Maximum \| Navistar, Inc. \| JDA
Commitments And Contingencies [Line Items]
Research and development expenses reimbursement	$ 10,000