Income Per Common Share (Computation Of Net Income (Loss) Per Share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Income Per Common Share [Abstract]
Net income attributed to Landauer, Inc.	$ 4,401	$ 3,643
Less: Income allocated to unvested restricted stock	23	18
Net income available to common stockholders	$ 4,378	$ 3,625
Basic weighted average shares outstanding	9,540	9,460
Net income per share - Basic	$ 0.46	$ 0.38
Effect of dilutive securities	$ 44	$ 32
Diluted weighted averages shares outstanding	9,584	9,492
Net income per share - Diluted	$ 0.46	$ 0.38
Dividends paid per share	$ 0.275	$ 0.275