Investment maturity period.

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- Definition

Number of Advertising displays as of the balance sheet date.

+ References

No definition available.

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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.

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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.

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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

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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 maximum useful life of a major finite-lived intangible asset class. A major class is composed of intangible assets that can be grouped together because they are similar either by their nature or by their use in the operations of a company.

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The minimum useful life of a major finite-lived intangible asset class. A major class is composed of intangible assets that can be grouped together because they are similar either by their nature or by their use in the operations of a company.

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- Definition

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

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No definition available.

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Significant Accounting Policies (Details Textual) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011 Y AdvertisingDisplay State Market	Dec. 31, 2010	Dec. 31, 2009
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expense related to stock	$ 11,650	$ 17,839	$ 12,462
Significant Accounting Policies (Textual) [Abstract]
Number of advertising displays	143,000
Number of states in which the company operates	44
Number of states in which the company operates logo sign business	21
Number of markets in which entity operates with transit advertising business	60
Investment maturity period	three months or less
Estimated useful lives of Intangible assets, Minimum	3
Estimated useful lives of Intangible assets, Maximum	15
Anti-dilutive shares	0	465,820	2,580,092
Stock options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expense related to stock	7,875
Performance-based stock incentive program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expense related to stock	3,535
Stock awards to directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expense related to stock	$ 240