Related Party Transactions (Schedule Of Related Party Transactions) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Sep. 30, 2015
Aquila [Member]
Related Party Transaction [Line Items]
Sales to related party	$ 2,653	$ 1	$ 3,067	$ 3,674
Purchases from related party	201	165	405	196
Amounts in accounts receivable	4,318		4,318		$ 2,795
Amounts in accounts payable	492		492		284
Nagase-Landauer, Ltd. [Member]
Related Party Transaction [Line Items]
Sales to related party	1,180	169	3,474	924
Purchases from related party	123	$ 472	817	$ 934
Amounts in accounts receivable	428		428		769
Amounts in accounts payable	$ 11		$ 11		$ 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
-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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-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
-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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