Mack-Cali Realty, L.P.'s Partners' Capital (Earnings Per Share) (Narrative) (Details) (USD $)	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Mack-Cali Realty, L.P's Partners' Capital [Abstract]
Stock options not included in the computations of diluted EPU	15,000	15,000	307,184
Unvested restricted stock outstanding	187,447	239,759	323,088	375,006
Common unit distributions per unit declared	$ 1.80	$ 1.80	$ 1.80

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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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Glossary Diluted Earnings Per Share

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+ Details

- 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.

+ References+ Details