Income Per Common Share (Computation Of Net Income (Loss) Per Share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Income Per Common Share [Abstract]
Net income attributed to Landauer, Inc.	$ 7,265	$ 4,055	$ 15,187	$ 11,979
Less: Income allocated to unvested restricted stock	20	20	59	67
Net income available to common stockholders	$ 7,245	$ 4,035	$ 15,128	$ 11,912
Basic weighted average shares outstanding	9,531	9,509	9,523	9,476
Net income per share - Basic	$ 0.76	$ 0.42	$ 1.59	$ 1.26
Effect of dilutive securities	$ 33	$ 25	$ 32	$ 27
Diluted weighted averages shares outstanding	9,564	9,534	9,555	9,503
Net income per share - Diluted	$ 0.76	$ 0.42	$ 1.58	$ 1.25
Dividends paid per share	$ 0.275	$ 0.275	$ 0.83	$ 1.100