Related Party Transactions (Schedule Of Related Party Transactions) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Sep. 30, 2016
Aquila [Member]
Related Party Transaction [Line Items]
Sales to related party	$ 3,347	$ 2,653	$ 8,848	$ 3,067
Purchases from related party	128	201	232	405
Amounts in accounts receivable	3,439		3,439		$ 1,910
Amounts in accounts payable	193		193		320
Nagase-Landauer, Ltd. [Member]
Related Party Transaction [Line Items]
Sales to related party	961	1,180	3,204	3,474
Purchases from related party	58	$ 123	687	$ 817
Amounts in accounts receivable	117		117		288
Amounts in accounts payable	$ 5		$ 5		$ 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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-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.3)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Subparagraph (SX 210.4-08.(k)(1))
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-Section 50
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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
-Publisher FASB
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-Publisher FASB
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