Revenue - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Dec. 31, 2019	Sep. 30, 2019
Capitalized Contract Cost [Line Items]
Current contract assets	$ 1,000	$ 600
Non-current contract assets	0	0
Current contract liabilities	1,433	741
Non-current contract liabilities	300	300
Revenue recognized included in contract liabilities		300
Current capitalized costs	84	85
Non-current capitalized costs	0	0
Incremental costs amortized	78
Impairment related to incremental costs capitalized	$ 0
Payments terms	30 days
Practical Expedient, Incremental Costs	true
Practical Expedient, Financing Component	true
Remaining Performance Obligation, Optional Exemption	true
Minimum
Capitalized Contract Cost [Line Items]
Amortization Period	3 years
Maximum
Capitalized Contract Cost [Line Items]
Amortization Period	6 years
Europe \| Maximum
Capitalized Contract Cost [Line Items]
Payments terms	90 days
TS
Capitalized Contract Cost [Line Items]
Current capitalized costs	$ 13	47
Non-current capitalized costs	31	$ 0
Incremental costs amortized	3
Impairment related to incremental costs capitalized	$ 0

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