Related Party Transactions (Schedule Of Related Party Transactions) (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Sep. 30, 2016
Aquila [Member]
Related Party Transaction [Line Items]
Sales to related party	$ 2,568	$ 396
Purchases from related party	74	(10)
Amounts in accounts receivable	2,888		$ 1,910
Amounts in accounts payable	394		320
Nagase-Landauer, Ltd. [Member]
Related Party Transaction [Line Items]
Sales to related party	1,241	1,098
Purchases from related party	310	$ 595
Amounts in accounts receivable	334		288
Amounts in accounts payable	$ 41		$ 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
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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
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