Income Per Common Share (Computation Of Net Income Per Share) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2010
Income Per Common Share [Abstract]
Net income attributed to Landauer, Inc.	$ 19,270	$ 24,538	$ 23,674
Less: Income allocated to unvested restricted stock	137	129	91
Net income available to common stockholders	$ 19,133	$ 24,409	$ 23,583
Basic weighted averages shares outstanding	9,389	9,395	9,310
Net income per share - Basic	$ 2.04	$ 2.60	$ 2.53
Effect of dilutive securities	48	82	39
Diluted weighted averages shares outstanding	9,437	9,477	9,349
Net income per share - Diluted	$ 2.03	$ 2.58	$ 2.52