Commitments and Contingencies - Textual (Details)				6 Months Ended
	Mar. 23, 2020 EUR (€)	Oct. 25, 2019 EUR (€)	Jun. 28, 2019 EUR (€)	Jun. 30, 2020 USD ($) ft²
Jupiter, Florida Headquarters Lease
Long-term Purchase Commitment [Line Items]
Area of building rented | ft²				4,900
Monthly rental rate | $				$ 9,700
Netherlands Office Lease
Long-term Purchase Commitment [Line Items]
Rent expense | $				$ 4,000
VTT Technical Research Centre of Finland Ltd
Long-term Purchase Commitment [Line Items]
Commitment to pay			€ 2,520,000
Commitment development period			3 years
Commitment success bonus award			€ 450,000
Commitment to pay, expanded		€ 690,000
Commitment to pay, expanded, period		1 year 6 months
Commitment to pay, additional	€ 700,000
Commitment to pay, additional coverage period	19 months
Commitments, right to terminate contract notice period	90 days