Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
ASSETS
Operating (including $1,666,691 and $1,226,918 of consolidated variable interest entities, respectively)	$ 6,758,728	$ 6,125,957
Construction-in-progress	769,882	599,260
Asset held for sale	0	33,856
Real estate, at cost, total	7,528,610	6,759,073
Less accumulated depreciation and amortization (including $236,391 and $209,239 of consolidated variable interest entities, respectively)	(1,828,845)	(1,729,234)
Net real estate	5,699,765	5,029,839
Cash and cash equivalents	22,850	23,368
Accounts and notes receivable, net	200,878	116,749
Mortgage notes receivable, net	30,429	29,904
Investment in real estate partnerships	23,925	14,864
Prepaid expenses and other assets	243,290	208,555
TOTAL ASSETS	6,221,137	5,423,279
Liabilities
Mortgages payable (including $461,873 and $439,120 of consolidated variable interest entities, respectively)	493,240	471,117
Capital lease obligations	71,565	71,590
Notes payable	320,718	279,151
Senior notes and debentures	2,377,939	1,976,594
Accounts payable and accrued expenses	206,441	201,756
Dividends payable	73,466	71,440
Security deposits payable	16,698	16,285
Other liabilities and deferred credits	175,464	115,817
Total liabilities	3,735,531	3,203,750
Commitments and contingencies (Note 6)
Redeemable noncontrolling interests	151,815	143,694
Shareholders’ equity
Common shares of beneficial interest, $.01 par, 100,000,000 shares authorized, 72,542,909 and 71,995,897 shares issued and outstanding, respectively	728	722
Additional paid-in capital	2,773,890	2,718,325
Accumulated dividends in excess of net income	(724,919)	(749,734)
Accumulated other comprehensive loss	(742)	(2,577)
Total shareholders’ equity of the Trust	2,208,954	1,976,733
Noncontrolling interests	124,837	99,102
Total shareholders’ equity	2,333,791	2,075,835
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	6,221,137	5,423,279
5.0% Series C Cumulative Redeemable Preferred
Shareholders’ equity
Preferred shares, authorized 15,000,000 shares, $.01 par	150,000	0
5.417% Series 1 Cumulative Convertible Preferred
Shareholders’ equity
Preferred shares, authorized 15,000,000 shares, $.01 par	$ 9,997	$ 9,997

Carrying amount as of the balance sheet date, net of allowance for doubtful accounts, of account and note receivables due from other than related parties.

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- Definition

Sum of the carrying values as of the balance sheet date of obligations incurred through that date, including liabilities incurred and payable to vendors for goods and services received, taxes, interest, rent and utilities, compensation costs, payroll taxes and fringe benefits (other than pension and postretirement obligations), contractual rights and obligations, and statutory obligations.