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Commitments and Contingencies - Narrative (Details) € in Thousands, £ in Thousands, ft² in Thousands, $ in Thousands													1 Months Ended	2 Months Ended	3 Months Ended	12 Months Ended
	Jul. 21, 2021 patent	Mar. 31, 2021 patent	Dec. 18, 2020 patent	Dec. 04, 2020 patent	Sep. 30, 2020 USD ($) patent	Jan. 10, 2020 USD ($) 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 (€)	Dec. 10, 2021 patent	Jan. 26, 2021 patent	Feb. 23, 2021 patent	Sep. 30, 2021 USD ($) ft²	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2021 EUR (€) ft²	Sep. 30, 2021 GBP (£) ft²
Leases
Annual base rent																$ 1,200
Tenant improvement allowances																1,000
Unamortized lease incentives																$ 400
Weighted average remaining lease term of operating leases																5 years 6 months			5 years 6 months	5 years 6 months
Weighted average discount rate of operating leases																3.20%			3.20%	3.20%
Right-of-use assets					$ 5,407											$ 7,056	$ 5,407
Operating lease liabilities																8,530
Lease liabilities, current portion					1,819											1,943	1,819
Lease liabilities, non-current portion					$ 5,327											6,588	5,327
Operating lease costs																2,200
Operating lease expense																2,200	2,200
Rent expense for operating leases																		$ 2,100
Operating lease payments																$ 2,300
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 related to 401(k) plan																$ 700	$ 400	$ 200
France
Leases
Annual base rent																484			€ 418
Netherlands
Leases
Annual base rent																222			191
United States
Leases
Annual base rent																195
Spain
Leases
Annual base rent																113			€ 97
United Kingdom
Leases
Annual base rent																151				£ 112
Other Current Liabilities
Leases
Unamortized lease incentives																100
Other Noncurrent Liabilities
Leases
Unamortized lease incentives																200
Pending Litigation \| General and administrative
Claims
Legal fees incurred related to third-party claims against customers																$ 1,000
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	€ 800
Pending Litigation \| USAA \| Wells Fargo
Claims
Number of patents allegedly infringed					2	2	3		5	4					4
Number of patents infringed \| patent						1	1
Amount awarded in damages to other party						$ 102,000	$ 200,000
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 \| PNC Bank
Claims
Number of patents allegedly infringed \| patent		2		2	2
Number of patents denied institution \| patent	6	2
Pending Litigation \| USAA \| PNC Bank \| Subsequent Event
Claims
Number of patents denied institution \| patent													4
Minimum
Leases
Remaining operating lease term																1 year			1 year	1 year
Maximum
Leases
Remaining operating lease term																9 years			9 years	9 years
Building \| Executive Offices and R&D Facility, San Diego
Leases
Office space subject to lease \| ft²																29			29	29