Table 3 - Summary of Aggregate Princip...(Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Aggregate principal payments of mortgage notes payable
2013	$ 107,735
2014	139,781
2015	76,858
2016	33,557
2017	101,529
Thereafter	31,746
Long-term Debt	$ 491,206	$ 584,245

Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year.

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