Related Party Transactions (Schedule Of Related Party Transactions) (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
Aquila [Member]
Related Party Transaction [Line Items]
Sales to related party	$ 3,388	$ 5,844	$ 6,271
Purchases from related party	559	647	890
Amounts in accounts receivable	1,910	2,795
Amounts in accounts payable	320	284
Nagase-Landauer, Ltd [Member]
Related Party Transaction [Line Items]
Sales to related party	4,613	1,924	1,341
Purchases from related party	1,013	1,189	$ 1,710
Amounts in accounts receivable	288	769
Amounts in accounts payable	$ 23	$ 33

For an unclassified balance sheet, amounts due from related parties including affiliates, employees, joint ventures, officers and stockholders, immediate families thereof, and pension funds.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Publisher FASB
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