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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Research and development (Details) $ in Thousands	3 Months Ended		12 Months Ended
Research and development (Details) $ in Thousands	Dec. 31, 2016 USD ($) Job	Jan. 02, 2016 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2016 USD ($)
Research and development [Abstract]
Cost of research and development program	$ 1,441	$ 860
Income statement credit	134	0
Income tax receivable	$ 667			$ 985
Minimum [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Credit percentage	11.00%
Maximum [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Credit percentage	14.50%
U.K. Regional Growth Fund [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Revenue from grants	$ 88	30
Research and development expense	$ 362	$ 165
Total grants awarded			$ 625
Number of jobs created or safeguarded \| Job	20