Total liquidation value of issued and outstanding preferred stock as of the balance sheet date.

No definition available.

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- Definition

Description of voting rights of common stock. Includes eligibility to vote and votes per share owned. Include also, if any, unusual voting rights.

+ References

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- Definition

The amount per share used to calculated dividend payments on preferred stock.

+ References

No definition available.

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- Definition

The per share liquidation preference (or restrictions) of nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) that has a preference in involuntary liquidation considerably in excess of the par or stated value of the shares. The liquidation preference is the difference between the preference in liquidation and the par or stated values of the share.

+ References

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- Definition

Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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- Definition

The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

+ References

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- Definition

Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

+ References

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- Definition

Description of voting rights of nonredeemable preferred stock. Includes eligibility to vote and votes per share owned. Include also, if any, unusual voting rights.

+ References

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Amount of stock repurchase plan authorized.

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No definition available.

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- Definition

Amount of decrease of par value, additional paid in capital (APIC) and retained earnings of common and preferred stock retired from treasury when treasury stock is accounted for under the par value method.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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- Definition

Number of shares of common and preferred stock retired from treasury during the period.

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Stockholders' Equity - Additional Information (Detail) (USD $)	12 Months Ended	0 Months Ended
	Dec. 31, 2014	Jul. 16, 1999	Dec. 31, 2013	Dec. 11, 2014
Class of Stock [Line Items]
Liquidation value of outstanding preferred stock	$ 3,649,000lamr_PreferredStockLiquidationValue
Preferred stock voting right	Series AA preferred stock is entitled to one vote per share and the Class A preferred stock is not entitled to vote
Class B common stock voting rights	Holders of Class B common stock have ten votes per share on all matters in which the holders of common stock are entitled to vote and holders of Class A common stock have one vote per share on such matters
Treasury stock retired shares	17,270,930us-gaap_TreasuryStockSharesRetired
Treasury stock retired value	896,818,000
Authorized amount of Stock repurchase	0
Treasury Stock [Member]
Class of Stock [Line Items]
Treasury stock retired shares	17,270,930
Treasury stock retired value	(896,818,000)
Additional Paid-in Capital [Member]
Class of Stock [Line Items]
Treasury stock retired value	896,801,000
Series AA Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, shares authorized	5,720	5,720	5,720
Preferred stock, par value	$ 0.001	$ 0.001	$ 0.001
Preferred stock, outstanding	5,720		5,720
Dividends paid to preferred stock		$ 15.95
Amount entitled		$ 638
Preferred Class A [Member]
Class of Stock [Line Items]
Preferred stock, shares authorized	0	1,000,000	10,000
Preferred stock, par value	$ 638	$ 638	$ 638
Preferred stock, outstanding	0	0	0
Dividends paid to preferred stock		$ 15.95
Amount entitled		$ 638
Common Class A [Member]
Class of Stock [Line Items]
Authorized amount of Stock repurchase				250,000,000
Common Class A [Member] \| Common Stock [Member]
Class of Stock [Line Items]
Treasury stock retired value	$ 17,000