Finite Lived Intangible Asset Useful Life Maximum

No definition available.

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- Definition

Finite Lived Intangible Asset Useful Life Minimum

+ References

No definition available.

+ Details

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- Definition

Investment maturity period.

+ References

No definition available.

+ Details

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- Definition

Number of Advertising displays as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

Number of markets in which the entity operates with transit advertising business as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

Number of states in which the entity operates with logo sign business as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

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

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- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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- Definition

The number of states the entity operates in as of the balance sheet date.

+ References

No definition available.

+ Details

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Significant Accounting Policies - Additional Information (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012 Billboard State Markets	Dec. 31, 2011	Dec. 31, 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of advertising displays	144,000
Number of states in which the company operates	44
Number of states in which the company operates logo sign business	22
Number of markets in which entity operates with transit advertising business	60
Estimated useful lives of Intangible assets, Minimum	3 years
Estimated useful lives of Intangible assets, Maximum	15 years
Anti-dilutive shares	0	0	465,820
Expenses related to stock	$ 14,466	$ 11,650	$ 17,839
Investment maturity period	Three months or less
LAMAR MEDIA CORP [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of advertising displays	144,000
Number of states in which the company operates	44
Number of states in which the company operates logo sign business	22
Stock options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expenses related to stock	6,249
Performance-based stock incentive program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expenses related to stock	7,970
Stock awards to directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expenses related to stock	$ 247