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           Mack-Cali Realty Corporation Stockholders' Equity (Earnings Per Share) (Narrative) (Details) (USD $) 
        In Thousands, except Per Share data  | 
        3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
| 
           Jun. 30, 2011 
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           Jun. 30, 2010 
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           Jun. 30, 2011 
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           Jun. 30, 2010 
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| Mack-Cali Realty Corporation Stockholders' Equity | ||||
| Dividends declared per common share | $ 0.45 | $ 0.45 | $ 0.90 | $ 0.9 | 
| Unvested Restricted Stock Outstanding | 157,681 | 216,802 | 157,681 | 216,802 | 
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- Definition 
          Aggregate dividends declared during the period for each share of common stock outstanding. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition 
          The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Details 
          
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