Stock-based Compensation (Tables)

6 Months Ended

Mar. 31, 2018

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Stock-Based Compensation Expenses

The Company’s stock-based compensation expenses were allocated to the following expense categories:

	Three Months Ended				Six Months Ended
	March 31,				March 31,
(Dollars in thousands)	2018		2017		2018		2017
Product costs	$	23	$	37	$	17	$	50
Research and development		179		123		337		248
Selling, general and administrative		899		722		1,649		1,373
Total	$	1,101	$	882	$	2,003	$	1,671

Assumptions Used in Stock Option Plans

	Three Months Ended						Six Months Ended
	March 31,						March 31,
	2018			2017			2018			2017
Risk-free interest rates		2.6	%		1.9	%		2.1	%		1.7	%
Expected life (years)		4.8			4.7			4.8			4.6
Expected volatility		33.0	%		34.1	%		33.0	%		34.4	%
Dividend yield		0.0	%		0.0	%		0.0	%		0.0	%

Schedule of Fair Value at the Date of Grant

The aggregate number of shares that could be awarded to our executives if the minimum, target and maximum performance goals are met, based on the fair value at the date of grant is as follows:

Performance Period	Minimum Shares		Target Shares		Maximum Shares
Fiscal 2016 – 2018		13,268		66,338		132,676
Fiscal 2017 – 2019		10,437		52,185		104,370