Related Party Transactions (Schedule Of Related Party Transactions) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2017	Mar. 31, 2016	Sep. 30, 2016
Aquila [Member]
Related Party Transaction [Line Items]
Sales to related party	$ 2,933	$ 18	$ 5,501	$ 414
Purchases from related party	30	214	104	204
Amounts in accounts receivable	4,069		4,069		$ 1,910
Amounts in accounts payable	114		114		320
Nagase-Landauer, Ltd. [Member]
Related Party Transaction [Line Items]
Sales to related party	1,002	1,196	2,243	2,294
Purchases from related party	319	$ 99	629	$ 694
Amounts in accounts receivable	294		294		288
Amounts in accounts payable	$ 52		$ 52		$ 23

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
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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