Commitments and Contingencies - Additional Information (Details) ft² in Thousands, € in Millions												9 Months Ended	11 Months Ended	12 Months Ended
	Nov. 17, 2020 patent	Sep. 30, 2020 USD ($) ft² patent	Apr. 28, 2020 patent	Jan. 10, 2020 USD ($) patent	Nov. 06, 2019 USD ($) patent day	Jul. 31, 2019 patent	Aug. 17, 2018 patent	Jul. 07, 2018 patent	Jun. 11, 2018 USD ($)	Jun. 11, 2018 EUR (€)	May 03, 2018 USD ($)	Sep. 30, 2020 USD ($) ft² patent	Dec. 07, 2020 USD ($)	Sep. 30, 2020 USD ($) ft²	Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2020 EUR (€) ft²	Sep. 30, 2020 GBP (£) ft²	Oct. 01, 2019 USD ($)
Leases
Annual base rent		$ 1,200,000										$ 1,200,000		$ 1,200,000
Tenant improvement allowances		1,000,000.0										1,000,000.0		1,000,000.0
Unamortized lease incentives		$ 500,000										$ 500,000		$ 500,000
Weighted average remaining lease term of operating leases		4 years 4 months 24 days										4 years 4 months 24 days		4 years 4 months 24 days			4 years 4 months 24 days	4 years 4 months 24 days
Weighted average discount rate of operating leases		4.70%										4.70%		4.70%			4.70%	4.70%
Right-of-use assets		$ 5,407,000										$ 5,407,000		$ 5,407,000					$ 6,800,000
Operating lease liabilities		7,146,000										7,146,000		7,146,000					$ 8,200,000
Lease liabilities, current portion		1,819,000										1,819,000		1,819,000
Lease liabilities, non-current portion		5,327,000										5,327,000		5,327,000
Operating lease costs														2,200,000
Operating lease expense														2,200,000
Rent expense for operating leases															$ 2,100,000	$ 1,700,000
Operating lease payments														$ 1,700,000
Claims
Company contribution, percent of designated deferral of eligible compensation														50.00%
Company contribution, percent of employee compensation eligible for company match														6.00%
Employer contribution amount														$ 420,000	$ 231,000	$ 123,000
Line of Credit | Revolving Credit Facility
Claims
Maximum borrowing capacity											$ 10,000,000.0
Interest rate floor											0.045
Minimum unrestricted cash and unused borrowing capacity											$ 15,000,000.0
Adjusted quick ratio requirement											1.75
Borrowings outstanding		0										0		0
Line of Credit | Revolving Credit Facility | Prime Rate
Claims
Basis spread on variable rate											0.25%
France
Leases
Annual base rent		400,000										400,000		400,000			€ 0.4
Netherlands
Leases
Annual base rent		300,000										300,000		300,000			0.3
United States
Leases
Annual base rent		200,000										200,000		200,000
Spain
Leases
Annual base rent		100,000										100,000		100,000			€ 0.1
United Kingdom
Leases
Annual base rent		143,000										143,000		143,000				£ 112,200
Other Current Liabilities
Leases
Unamortized lease incentives		100,000										100,000		100,000
Other Noncurrent Liabilities
Leases
Unamortized lease incentives		$ 400,000										$ 400,000		400,000
Pending Litigation | General and administrative
Claims
Legal fees incurred related to third-party claims against customers														$ 3,200,000
Pending Litigation | UrbanFT
Claims
Number of patents allegedly infringed | patent			2			5
Number of patents invalid | patent			2
Number of patents not infringed | patent			2
Pending Litigation | Global Equity & Corporate Consulting, S.L.- Breach of Services Agreement | ICAR
Claims
Amount claimed during court proceedings									$ 900,000	€ 0.8
Pending Litigation | USAA | Wells Fargo
Claims
Number of patents allegedly infringed				2	3		5	4				4
Number of patents infringed | patent				1	1
Amount awarded in damages to other party				$ 102,000,000	$ 200,000,000
Number of patents dropped | patent							2
Number of patents invalid | patent							1
Number of patents instituted | patent												3
Number of patents denied institution | patent												1
Pending Litigation | USAA | Wells Fargo | Subsequent Event
Claims
Number of patents allegedly infringed | patent	4
Amount awarded in damages to other party													$ 0
Number of patents denied institution | patent	3
Pending Litigation | USAA | PNC Bank
Claims
Number of patents allegedly infringed | patent		2
Minimum
Leases
Remaining operating lease term		1 year										1 year		1 year			1 year	1 year
Maximum
Leases
Remaining operating lease term		8 years										8 years		8 years			8 years	8 years
Building | Executive Offices and R&D Facility, San Diego
Leases
Office space subject to lease | ft²		29										29		29			29	29