Income Taxes - U.S. and Foreign Components of Earnings (Loss) Before Income Taxes (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Components Of Earnings From Continuing Operations Before Income Taxes And Provision For Income Taxes [Line Items]
U.S.	$ 20,444	$ 16,641	$ (59,353)
Foreign	(1,147)	(1,468)	(4,218)
Income (loss) before income tax expense	19,297	15,173	(63,571)
LAMAR MEDIA CORP [Member]
Components Of Earnings From Continuing Operations Before Income Taxes And Provision For Income Taxes [Line Items]
U.S.	20,780	16,999	(59,193)
Foreign	(1,147)	(1,468)	(4,218)
Income (loss) before income tax expense	$ 19,633	$ 15,531	$ (63,411)

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The portion of earnings or loss from continuing operations before income taxes that is attributable to domestic operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(h)(1)(i))

-URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e23780-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph h

-Subparagraph 1(i)

-Article 4

+ Details

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- Definition

The portion of earnings or loss from continuing operations before income taxes that is attributable to foreign operations, which is defined as Income or Loss generated from operations located outside the entity's country of domicile.

+ References

+ Details

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- Definition

Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest.

+ References

+ Details

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