Other Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Sep. 30, 2018
Other Assets, Noncurrent [Abstract]
Pension surplus	$ 4,611	$ 5,257
Long term receivables	1,934	2,209
Long term prepaid expenses and other assets	3,619	4,648
Total	$ 10,164	$ 12,114