| **CONSOLIDATED BALANCE SHEETS (Parentheticals) (USD $)In Thousands, except Per Share data, unless otherwise specified** | Mar. 31, 2013 | Dec. 31, 2012 |
|-------------------------------------------------------------------------------------------------------------------------|---------------|---------------|
| Deferred loan and senior notes costs, accumulated amortization                                                          | $ 5,001       | $ 4,554       |
| Common Stock - Class A [Member]                                                                                         |          |          |
| Common Stock, no par                                                                                                    | $ 0.00        | $ 0.00        |
| Common Stock, Shares Authorized                                                                                         | 100,000       | 100,000       |
| Common Stock, Shares Issued                                                                                             | 38,396        | 38,534        |
| Common Stock, Shares Outstanding                                                                                        | 38,297        | 38,357        |
| Treasury Stock, Shares                                                                                                  | 99            | 177           |
| Common Stock - Class B [Member]                                                                                         |          |          |
| Common Stock, no par                                                                                                    | $ 0.00        | $ 0.00        |
| Common Stock, Shares Authorized                                                                                         | 10,000        | 10,000        |
| Common Stock, Shares Issued                                                                                             | 3,167         | 3,169         |
| Common Stock, Shares Outstanding                                                                                        | 3,167         | 3,169         |
| Treasury Stock, Shares                                                                                                  | 0             | 0             |

| X                                                                                                                                                                                                                                                                                                                                                                        |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The accumulated amount of amortization of long-term deferred finance costs capitalized at the end of the reporting period.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Issuance value per share of no-par value common stock; generally not indicative of the fair market value per share.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The maximum number of common shares permitted to be issued by an entity's charter and bylaws.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.
+ References
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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.
+ References
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