Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2012

Accounting Policies [Abstract]

Property, Plant and Equipment, Policy [Policy Text Block]

Operating Properties

Operating properties are carried at historical cost less accumulated depreciation and impairment losses. The cost of operating properties reflects their purchase price or development cost. Acquisition related costs are expensed as incurred. Costs incurred for the renovation and betterment of an operating property are capitalized to the Company’s investment in that property. Ordinary repairs and maintenance are expensed as incurred; major replacements and betterments, which improve or extend the life of the asset, are capitalized and depreciated over their estimated useful lives. Fully-depreciated assets are removed from the accounts.

Depreciation and Amortization

The costs of buildings and improvements are depreciated using the straight-line method based on the following useful lives: buildings and improvements (five to 55 years) and tenant improvements (the shorter of the lease term or the life of the asset).

The Company's 2011 consolidated statement of operations contained an out of period depreciation and amortization expense adjustment of $4.7 million relating to intangible assets representing tenant relationships and in-place leases that should have been written off in prior periods. This resulted in the overstatement of depreciation and amortization expense by $4.7 million in 2011. During the year ended December 31, 2010, depreciation and amortization expense was overstated by $1.7 million and was understated by $1.4 million, $1.8 million, $1.7 million and $1.5 million during the years ended December 31, 2009, 2008, 2007, and 2006, respectively. As management believes that this error was not material to prior years' consolidated financial statements and that the impact of recording the error during 2011 was not material to the Company's consolidated financial statements, the Company recorded the related adjustment during 2011.

Schedule of Other Assets [Table]

Other Assets

Other assets is comprised of the following (in thousands):

	December 31,
	2012		2011
Prepaid Ground Rent	$	7,527	$	7,615
Prepaid Real Estate Taxes	8,116		7,983
Rent inducements, net	7,101		7,572
Cash surrender value of life insurance	11,515		9,261
Restricted cash	4,354		2,528
Marketable securities	2,366		2,366
Prepaid insurance	2,370		2,589
Furniture, fixtures and equipment	437		634
Deposits on future settlements	1,129		3,884
Others	8,410		8,726
Total	$	53,325	$	53,158

Schedule of Capitalized Salaries Including Bonuses and Benefits [Table Text Block]

During the years ended December 31, 2012, 2011 and 2010, the Company's internal direct construction costs are comprised entirely of capitalized salaries. The following table shows the amount of compensation expense (including bonuses and benefits) capitalized for the years presented (in thousands):

	December 31,
	2012		2011		2010
Development	$	57	$	—	$	2,331
Redevelopment	353		—		127
Tenant Improvements	4,259		4,034		1,395
Total	$	4,669	$	4,034	$	3,853

Fair value of liabilities on recurring basis

	Fair Value Measurements at Reporting Date Using:
	December 31,		Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Unobservable Inputs
Description	2012		(Level 1)		(Level 2)		(Level 3)
Recurring
Liabilities:
Interest Rate Swaps	$	14,210	$	—	$	14,210	$	—

The following table sets forth the Company’s financial liabilities that were accounted for at fair value on a recurring basis as of December 31, 2011 (in thousands):

	Fair Value Measurements at Reporting Date Using:
	December 31,		Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Unobservable Inputs
Description	2011		(Level 1)		(Level 2)		(Level 3)
Recurring
Liabilities:
Interest Rate Swaps	$	3,886	$	—	$	3,886	$	—

Held-to-maturity securities

The following table sets forth the details of the remaining available-for-sale securities sold during 2012 (in thousands):

	Available-for-sale Securities Sold
	Cash Received		Principal Amount		Gain (loss)
Available-for-sale securities	$	106,009	$	106,169	$	(160	)

The Company did not hold any available-for-sale securities as of December 31, 2012 or December 31, 2011.