Segment Information (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2016 USD ($)	Mar. 31, 2015 USD ($)	Mar. 31, 2016 USD ($) segment	Mar. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)
Segment Reporting Information [Line Items]
Reporting segments | segment			3
Consolidated revenues	$ 38,082	$ 38,139	$ 74,612	$ 75,686
Consolidated operating income	7,217	5,630	13,469	11,771
Consolidated Assets	202,602		202,602		$ 208,744
Eliminations [Member]
Segment Reporting Information [Line Items]
Consolidated Assets	(28,418)		(28,418)		(26,091)
Radiation Measurement [Member]
Segment Reporting Information [Line Items]
Consolidated revenues	25,520	27,246	50,224	53,737
Consolidated operating income	9,969	9,414	18,867	18,798
Consolidated Assets	138,156		138,156		142,850
Medical Physics [Member]
Segment Reporting Information [Line Items]
Consolidated revenues	10,033	8,561	19,386	17,045
Consolidated operating income	918	321	1,696	939
Consolidated Assets	45,094		45,094		43,677
Medical Products [Member]
Segment Reporting Information [Line Items]
Consolidated revenues	2,529	2,332	5,002	4,904
Consolidated operating income	432	244	922	578
Consolidated Assets	47,770		47,770		$ 48,308
Corporate [Member]
Segment Reporting Information [Line Items]
Consolidated operating income	$ (4,102)	$ (4,349)	$ (8,016)	$ (8,544)