Summary Of Significant Accounting Policies (Consolidated Statement Balance Sheets) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Sep. 30, 2011
Current assets:
Cash and cash equivalents	$ 6,761	$ 8,638	$ 8,922	$ 11,466	$ 8,672	$ 6,620	$ 9,204	$ 14,927	$ 15,675	$ 6,162
Receivables, net of allowances	34,707	34,084	34,821	33,512	37,839	34,328	35,940	35,912	34,686
Inventories	6,687	7,770	7,509	8,301	9,729	9,739	9,718	9,199	8,725
Deferred income tax asset - current	2,369	1,617	1,627	1,626	1,626	1,644	1,724	1,858	1,799
Prepaid income taxes	1,836	5,498	2,243	2,374	3,270	4,403	4,976	836	2,141
Prepaid expenses and other current assets	1,973	3,164	2,994	3,070	1,869	2,421	1,928	2,015	1,561
Current assets	54,333	60,771	58,116	60,349	63,005	59,155	63,490	64,747	64,587
Property, plant and equipment, at cost:
Total property, plant and equipment cost	104,010	105,761	104,822	104,316	107,446	106,248	105,883	103,330	101,375
Accumulated depreciation and amortization	(57,253)	(57,369)	(55,275)	(53,407)	(55,514)	(53,326)	(51,256)	(49,125)	(46,983)
Net property, plant and equipment	46,757	48,392	49,547	50,909	51,932	52,922	54,627	54,205	54,392
Equity in joint ventures	23,835	23,744	23,356	22,600	23,234	21,314	21,721	22,115	24,030
Goodwill	43,218	44,645	86,384	86,529	84,436	83,833	106,746	107,001	106,717
Intangible assets, net of accumulated amortization	14,077	14,663	36,198	37,022	37,011	37,637	35,791	36,543	37,202
Dosimetry devices, net of accumulated depreciation	3,958	3,805	4,117	4,109	4,156	4,624	4,883	5,028	4,724
Other assets		24,204	10,839	10,659	10,932	9,261	9,058	8,941	8,619
ASSETS	216,586	220,224	268,557	272,177	274,706	268,746	296,316	298,580	300,271
Current liabilities:
Accounts payable	6,248	5,611	6,830	6,036	6,310	5,490	6,541	6,637	9,656
Dividends payable	5,329	5,380	5,352	5,433	5,419	5,389	5,403	5,342	5,345
Deferred contract revenue	14,750	16,970	14,420	14,372	14,509	14,646	15,213	15,865	15,866
Accrued compensation and related costs	7,132	6,849	7,176	6,160	8,207	7,146	6,938	5,520	8,124
Other accrued expenses	8,538	8,317	6,651	6,727	8,025	9,308	8,217	7,626	7,490
Current liabilities	44,728	43,127	40,429	38,728	42,470	41,979	42,312	40,990	46,481
Non-current liabilities:
Long-term debt	133,585	138,285	138,285	143,785	142,785	139,560	143,260	145,847	141,347
Pension and postretirement obligations	19,475	13,588	13,331	13,308	13,047	17,655	17,821	17,690	17,586
Deferred income taxes	509	(1,382)	8,785	8,286	7,899	8,096	14,159	13,727	13,717
Uncertain income tax liabilities	3,284	3,193	3,283	3,131	3,203	2,963	2,963	2,576	2,352
Other non-current liabilities	1,271	1,067	1,221	1,425	290	271	266	326	386
Non-current liabilities	158,124	154,751	164,905	169,935	167,224	168,545	178,469	180,166	175,388
Commitments and Contingencies
STOCKHOLDERS' EQUITY:
Common stock	958	962	963	962	958	959	956	955	949
Additional paid in capital	40,317	40,392	39,755	39,653	39,465	39,034	37,063	36,587	35,898
Accumulated other comprehensive loss	(10,148)	(4,318)	(4,098)	(4,578)	(4,408)	(7,960)	(7,446)	(5,934)	(5,375)	(3,240)
Retained earnings	(18,873)	(16,321)	25,293	25,752	27,412	24,922	43,796	44,627	45,596
Landauer, Inc. stockholders' equity	12,254	20,715	61,913	61,789	63,427	56,955	74,369	76,235	77,068
Noncontrolling interest	1,480	1,631	1,310	1,725	1,585	1,267	1,166	1,189	1,334
Stockholders' equity	13,734	22,346	63,223	63,514	65,012	58,222	75,535	77,424	78,402	80,426
LIABILITIES AND STOCKHOLDERS' EQUITY	216,586	220,224	268,557	272,177	274,706	268,746	296,316	298,580	300,271
Previously Reported [Member]
Current assets:
Cash and cash equivalents		11,154	10,991	13,272	11,184	8,997	11,054	16,497	17,633	7,914
Receivables, net of allowances		34,750	35,487	34,178	38,419	34,807	36,419	36,391	35,165
Inventories		7,734	7,509	8,301	9,539	9,487	9,718	9,199	8,638
Deferred income tax asset - current		2,303	2,313	2,312	2,312	2,259	2,339	2,473	2,414
Prepaid income taxes		6,383	2,411	2,671	3,132	3,513	4,902	698	2,148
Prepaid expenses and other current assets		3,002	2,832	2,908	1,707	2,259	1,928	2,015	1,561
Current assets		65,326	61,543	63,642	66,293	61,322	66,360	67,273	67,559
Property, plant and equipment, at cost:
Total property, plant and equipment cost		105,761	104,822	104,316	107,446	106,248	105,883	103,330	101,375
Accumulated depreciation and amortization		(57,369)	(55,275)	(53,407)	(55,514)	(53,326)	(51,256)	(49,125)	(46,983)
Net property, plant and equipment		48,392	49,547	50,909	51,932	52,922	54,627	54,205	54,392
Equity in joint ventures		23,744	23,356	22,600	23,942	22,735	22,683	22,664	24,108
Goodwill		44,645	86,384	86,529	84,436	83,833	106,746	107,001	106,717
Intangible assets, net of accumulated amortization		14,663	36,198	37,022	37,161	37,987	36,091	36,793	37,402
Dosimetry devices, net of accumulated depreciation		5,409	5,734	5,739	5,798	6,221	6,436	6,537	6,189
Other assets		20,539	7,621	7,704	7,271	5,837	6,101	6,366	5,758
ASSETS		222,718	270,383	274,145	276,833	270,857	299,044	300,839	302,125
Current liabilities:
Accounts payable		5,611	6,830	6,036	6,310	5,490	6,541	6,637	9,656
Dividends payable		5,380	5,352	5,433	5,419	5,389	5,403	5,342	5,345
Deferred contract revenue		16,772	13,120	13,572	13,181	13,572	14,413	15,065	14,947
Accrued compensation and related costs		6,849	7,176	6,160	8,207	7,146	6,938	5,520	8,260
Other accrued expenses		7,776	6,125	6,217	7,531	8,863	7,789	7,215	7,096
Current liabilities		42,388	38,603	37,418	40,648	40,460	41,084	39,779	45,304
Non-current liabilities:
Long-term debt		138,285	138,285	143,785	142,785	139,560	143,260	145,847	141,347
Pension and postretirement obligations		13,588	13,331	13,308	13,047	17,655	17,821	17,690	17,586
Deferred income taxes		656	10,823	10,324	9,817	10,118	16,179	15,745	15,733
Uncertain income tax liabilities		351	529	465	625	621	840	672	667
Other non-current liabilities		1,067	1,221	1,425	290	271	266	326	386
Non-current liabilities		153,947	164,189	169,307	166,564	168,225	178,366	180,280	175,719
Commitments and Contingencies
STOCKHOLDERS' EQUITY:
Common stock		962	963	962	958	959	956	955	949
Additional paid in capital		40,392	39,755	39,653	39,465	39,034	37,063	36,587	35,898
Accumulated other comprehensive loss		(4,360)	(4,092)	(4,547)	(4,456)	(7,866)	(7,324)	(5,788)	(5,272)
Retained earnings		(12,299)	29,606	29,582	32,012	28,721	47,685	47,793	48,142
Landauer, Inc. stockholders' equity		24,695	66,232	65,650	67,979	60,848	78,380	79,547	79,717
Noncontrolling interest		1,688	1,359	1,770	1,642	1,324	1,214	1,233	1,385
Stockholders' equity		26,383	67,591	67,420	69,621	62,172	79,594	80,780	81,102
LIABILITIES AND STOCKHOLDERS' EQUITY		$ 222,718	$ 270,383	$ 274,145	$ 276,833	$ 270,857	$ 299,044	$ 300,839	$ 302,125