Related Party Transactions (Schedule Of Related Party Transactions) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2016	Mar. 31, 2015	Sep. 30, 2015
Aquila [Member]
Related Party Transaction [Line Items]
Sales to related party	$ 18	$ 1,870	$ 414	$ 3,673
Purchases from related party	214	23	204	31
Amounts in accounts receivable	1,919		1,919		$ 2,795
Amounts in accounts payable	173		173		284
Nagase-Landauer, Ltd. [Member]
Related Party Transaction [Line Items]
Sales to related party	1,196	109	2,294	755
Purchases from related party	99	$ 196	694	$ 462
Amounts in accounts receivable	819		819		769
Amounts in accounts payable	$ 51		$ 51		$ 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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-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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