Equity and Stock-based Compensation Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2018	Mar. 31, 2017	Mar. 28, 2018	Sep. 30, 2017
Equity [Abstract]
Share-based compensation expense	$ 200	$ 300	$ 463	$ 624
Authorized stock repurchase amount					$ 4,000
Common stock, par value (USD per share)	$ 0.01		$ 0.01		$ 0.01	$ 0.01
Shares repurchased (in shares)			0