Income Per Common Share (Computation Of Net Income (Loss) Per Share) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Sep. 30, 2014	Mar. 09, 2015
Earnings Per Share [Line Items]
Net income attributed to Landauer, Inc.	$ 4,377us-gaap_NetIncomeLoss	$ 3,821us-gaap_NetIncomeLoss
Less: Income allocated to unvested restricted stock	29	46
Net income available to common stockholders	4,348	3,775
Basic weighted average shares outstanding	9,446	9,422
Net income per share - Basic	$ 0.46us-gaap_EarningsPerShareBasic	$ 0.40us-gaap_EarningsPerShareBasic
Effect of dilutive securities	$ 28us-gaap_DilutiveSecurities	$ 45us-gaap_DilutiveSecurities
Diluted weighted averages shares outstanding	9,474	9,467
Net income per share - Diluted	$ 0.46us-gaap_EarningsPerShareDiluted	$ 0.40us-gaap_EarningsPerShareDiluted
Dividends paid per share	$ 0.55	$ 0.55	$ 0.55
Subsequent Event [Member]
Earnings Per Share [Line Items]
Dividends declared				$ 0.275

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Aggregate dividends paid during the period for each share of common stock outstanding.

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Amount of increase (decrease) to net income used for calculating diluted earnings per share (EPS), resulting from the assumed exercise stock options, restrictive stock units (RSUs), convertible preferred stock of an employee stock ownership plan (ESOP), and other dilutive convertible securities.

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The per share amount of a dividend declared, but not paid, as of the financial reporting date.

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

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The aggregate value of preferred stock dividends and other adjustments necessary to derive net income apportioned to common stockholders.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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