Income Per Common Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2011
Income Per Common Share [Abstract]
Net income attributed to Landauer, Inc.	$ 8,559	$ (13,753)	$ 5,153	$ 4,877	$ 669	$ 6,566	$ 7,110	$ 4,925	$ 4,836	$ 19,270	$ 24,538
Less: Income allocated to unvested restricted stock									165	137	129
Net income available to common stockholders									$ 4,671	$ 19,133	$ 24,409
Basic weighted averages shares outstanding	9,462,000	9,439,000	9,417,000	9,336,000	9,397,000	9,371,000	9,361,000	9,348,000	9,434,000	9,389,000	9,395,000
Net income per share - Basic	$ 0.90	$ (1.46)	$ 0.54	$ 0.52	$ 0.07	$ 0.70	$ 0.76	$ 0.52	$ 0.50	$ 2.04	$ 2.60
Effect of dilutive securities									48,000	48,000	82,000
Diluted weighted averages shares outstanding	9,506,000	9,439,000	9,462,000	9,385,000	9,456,000	9,412,000	9,402,000	9,385,000	9,482,000	9,437,000	9,477,000
Net income per share - Diluted	$ 0.90	$ (1.46)	$ 0.54	$ 0.52	$ 0.07	$ 0.69	$ 0.75	$ 0.52	$ 0.49	$ 2.03	$ 2.58