Related Party Transactions (Schedule Of Related Party Transactions) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Sep. 30, 2014
Aquila [Member]
Related Party Transaction [Line Items]
Sales to related party	$ 1		$ 3,674	$ 681
Purchases from related party	165	$ 348	196	601
Amounts in accounts receivable	875		875		$ 3,799
Amounts in accounts payable	161		161		227
Nagase-Landauer, Ltd. [Member]
Related Party Transaction [Line Items]
Sales to related party	169	276	924	897
Purchases from related party	472	$ 672	934	$ 1,472
Amounts in accounts receivable	158		158		27
Amounts in accounts payable	$ 65		$ 65		$ 60

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

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