Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
ASSETS
Operating (including $1,639,486 and $1,211,605 of consolidated variable interest entities, respectively)	$ 6,950,188	$ 6,125,957
Construction-in-progress (including $43,393 and $15,313 of consolidated variable interest entities, respectively)	684,873	599,260
Assets held for sale	0	33,856
Real estate, at cost, total	7,635,061	6,759,073
Less accumulated depreciation and amortization (including $247,410 and $209,239 of consolidated variable interest entities, respectively)	(1,876,544)	(1,729,234)
Net real estate	5,758,517	5,029,839
Cash and cash equivalents	15,188	23,368
Accounts and notes receivable	209,877	116,749
Mortgage notes receivable, net	30,429	29,904
Investment in real estate partnerships	23,941	14,864
Prepaid expenses and other assets	237,803	208,555
TOTAL ASSETS	6,275,755	5,423,279
Liabilities
Mortgages payable (including $460,372 and $439,120 of consolidated variable interest entities, respectively)	491,505	471,117
Capital lease obligations	71,556	71,590
Notes payable	320,265	279,151
Senior notes and debentures	2,401,440	1,976,594
Accounts payable and accrued expenses	196,332	201,756
Dividends payable	75,931	71,440
Security deposits payable	16,667	16,285
Other liabilities and deferred credits	169,388	115,817
Total liabilities	3,743,084	3,203,750
Commitments and contingencies (Note 7)
Redeemable noncontrolling interests	141,157	143,694
Shareholders’ equity
Common shares of beneficial interest, $.01 par, 100,000,000 shares authorized, 73,090,877 and 71,995,897 shares issued and outstanding, respectively	733	722
Additional paid-in capital	2,855,321	2,718,325
Accumulated dividends in excess of net income	(749,367)	(749,734)
Accumulated other comprehensive income (loss)	22	(2,577)
Total shareholders’ equity of the Trust	2,266,706	1,976,733
Noncontrolling interests	124,808	99,102
Total shareholders’ equity	2,391,514	2,075,835
TOTAL LIABILITIES AND SHAREHOLDERS’ EQUITY	6,275,755	5,423,279
5.0% Series C Cumulative Redeemable Preferred shares
Shareholders’ equity
5.417% Series 1 Cumulative Convertible Preferred Shares, (stated at liquidation preference $25 per share), 399,896 shares issued and outstanding	150,000	0
5.417% Series 1 Cumulative Convertible Preferred shares
Shareholders’ equity
5.417% Series 1 Cumulative Convertible Preferred Shares, (stated at liquidation preference $25 per share), 399,896 shares issued and outstanding	$ 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.