Summary of Significant Accounting Policies - Revenue Recognition (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2019	Oct. 01, 2018	Sep. 30, 2018
Capitalized Contract Cost [Line Items]
Current contract assets	$ 600	$ 1,100
Non-current contract assets	0	0
Current contract liabilities	741	900	$ 1,197
Non-current contract liabilities	300	0
Revenue recognized included in contract liabilities	800
Current capitalized costs	85	71
Non-current capitalized costs	0	0
Incremental costs amortized	235
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	$ 47	60
Non-current capitalized costs	0	$ 0
Incremental costs amortized	13
Impairment related to incremental costs capitalized	$ 0

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