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Consolidated Balance Sheets (Parenthetical) (USD $)
In Thousands, except Share data, unless otherwise specified |
Mar. 31, 2013
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Dec. 31, 2012
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| Statement of Financial Position [Abstract] | ||
| Accounts receivable, allowance for doubtful accounts | $ 5,351 | $ 4,694 |
| Preferred Shares of beneficial interest, par value (in dollars per share) | $ 0.01 | $ 0.01 |
| Preferred Shares of beneficial interest, shares authorized | 25,000,000 | 25,000,000 |
| Preferred Shares of beneficial interest, shares issued | 12,821,667 | 12,821,667 |
| Preferred Shares of beneficial interest, shares outstanding | 12,821,667 | 12,821,667 |
| Common Shares of beneficial interest, par value (in dollars per share) | $ 0.01 | $ 0.01 |
| Common Shares of beneficial interest, shares authorized | 125,000,000 | 125,000,000 |
| Common Shares of beneficial interest, shares issued | 85,758,438 | 80,952,986 |
| Common Shares of beneficial interest, shares outstanding | 85,758,438 | 80,952,986 |
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- Definition
For an unclassified balance sheet, a valuation allowance for receivables due a company that are expected to be uncollectible. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Face amount or stated value of common stock per share; generally not indicative of the fair market value per share. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The maximum number of common shares permitted to be issued by an entity's charter and bylaws. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- 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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Face amount or stated value per share of nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer); generally not indicative of the fair market value per share. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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