Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011
CASH FLOWS FROM OPERATING ACTIVITIES:
Net Loss	$ (9,240)	$ (4,489)
Adjustments to Reconcile Net Loss to Net Cash Provided by Operating Activities:
Depreciation	45,445	39,201
Amortization of Deferred Financing Costs	1,622	2,085
Other Amortization	14,704	15,891
Impairment of Real Estate, Net	1,101	(3,942)
Provision for Bad Debt	550	563
Equity in Income of Joint Ventures	(128)	(135)
Distributions from Joint Ventures	27	161
Gain on Sale of Real Estate	(7,614)	(6,279)
Gain on Change in Control of Interests	(776)	(689)
Loss from Retirement of Debt	6,222	4,099
Prepayment Penalties and Fees Associated with Retirement of Debt	(440)	(1,194)
Mark-to-Market Loss on Interest Rate Protection Agreements	305	188
Equity in Income of Other Real Estate Partnerships	(3,566)	(7,707)
Distributions from Investment in Other Real Estate Partnerships	3,566	7,707
Decrease in Tenant Accounts Receivable, Prepaid Expenses and Other Assets, Net	3,223	714
Increase in Deferred Rent Receivable	(1,704)	(3,971)
Increase (Decrease) in Accounts Payable, Accrued Expenses, Other Liabilities, Rents Received in Advance and Security Deposits	1,571	(9,862)
Decrease in Restricted Cash		101
Payments of Premiums and Discounts Associated with Senior Unsecured Notes	(2,847)	(27)
Net Cash Provided by Operating Activities	52,021	32,415
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of and Additions to Investment in Real Estate and Lease Costs	(83,626)	(35,969)
Net Proceeds from Sales of Investments in Real Estate	22,002	24,655
Investments in and Advances to Other Real Estate Partnerships	(7,970)	(58,704)
Distributions from Other Real Estate Partnerships in Excess of Equity in Income	8,047	108,018
Contributions to and Investments in Joint Ventures	(184)	(16)
Distributions from Joint Ventures		108
Repayment of Notes Receivable	8,306	10,049
Decrease in Lender Escrows		88
Net Cash (Used In) Provided by Investing Activities	(53,425)	48,229
CASH FLOWS FROM FINANCING ACTIVITIES:
Debt and Equity Issuance Costs	(287)	(1,701)
Unit Contributions	18,063	202,845
Preferred Unit Distributions	(9,525)	(9,874)
Repurchase and Retirement of Restricted Units	(855)	(1,001)
Payments on Interest Rate Swap Agreement	(572)	(292)
Proceeds from Origination on Mortgage Loans Payable		132,463
Repayments on Mortgage and Other Loans Payable	(17,432)	(60,148)
Repayments on Senior Unsecured Notes	(148,310)	(56,419)
Proceeds from Unsecured Credit Facility	241,000	101,500
Repayments on Unsecured Credit Facility	(84,000)	(378,553)
Net Cash Used in Financing Activities	(1,918)	(71,180)
Net Effect of Exchange Rate Changes on Cash and Cash Equivalents	(1)	36
Net (Decrease) Increase in Cash and Cash Equivalents	(3,322)	9,464
Cash and Cash Equivalents, Beginning of Period	7,624	22,484
Cash and Cash Equivalents, End of Period	$ 4,301	$ 31,984