Quarterly Financial Data (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
Quarterly Financial Data [Abstract]
Total revenues	$ 36,773	$ 37,854	$ 38,082	$ 36,530	$ 40,161	$ 35,467	$ 38,139	$ 37,547	$ 149,239	$ 151,314	$ 155,062
Gross profit	17,690	19,518	19,755	18,515	20,759	18,646	19,528	19,796	75,478	78,729	80,907
Operating income (loss)	5,459	7,713	7,217	6,252	6,817	5,111	5,630	6,141	26,641	23,699	(39,987)
Net income attributed to Landauer, Inc.	$ 2,566	$ 7,265	$ 4,279	$ 3,643	$ 2,564	$ 4,055	$ 3,547	$ 4,377	$ 17,753	$ 14,543	$ (25,203)
Basic net income (loss) per share	$ 0.27	$ 0.76	$ 0.45	$ 0.38	$ 0.27	$ 0.42	$ 0.37	$ 0.46	$ 1.86	$ 1.52	$ (2.65)
Diluted net income (loss) per share	$ 0.26	$ 0.76	$ 0.45	$ 0.38	$ 0.27	$ 0.42	$ 0.37	$ 0.46	$ 1.85	$ 1.52	$ (2.65)
Weighted average basic shares outstanding	9,532,000	9,531,000	9,518,000	9,460,000	9,533,000	9,509,000	9,493,000	9,446,000	9,526,000	9,511,000	9,524,000
Weighted average diluted shares outstanding	9,584,000	9,564,000	9,550,000	9,492,000	9,570,000	9,534,000	9,520,000	9,474,000	9,569,000	9,540,000	9,524,000
Goodwill and other intangible assets impairment charge											$ 62,188
Reorganization expenses					$ 1,041				$ 0	$ 1,041	$ 3,802
Impact of reorganization expenses on diluted net loss per share					$ (0.05)