Divestiture of Surefly	12 Months Ended
Dec. 31, 2020
Discontinued Operations and Disposal Groups [Abstract]
Divestiture of Surefly	DIVESTITURE OF SUREFLYOn November 27, 2019, the Company completed the sale of SureFly™ for $4.0 million. The gain on divestiture was $3.7 million, net of selling costs of $0.3 million. SureFly was the Company's hybrid electrically powered vertical takeoff and landing aircraft project. The Company had no revenues associated with SureFly in 2019. Operating expenses associated with the development of Surefly were $1.4 million in 2019.

The entire disclosure for business combinations, including leverage buyout transactions (as applicable), and divestitures. This may include a description of a business combination or divestiture (or series of individually immaterial business combinations or divestitures) completed during the period, including background, timing, and assets and liabilities recognized and reclassified or sold. This element does not include fixed asset sales and plant closings.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-URI http://asc.fasb.org/subtopic&trid=2122178

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-URI http://asc.fasb.org/topic&trid=2303972

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