Consolidated Balance Sheets (USD $) In Thousands	Sep. 30, 2011	Dec. 31, 2010
ASSETS
Real estate, at cost	$ 12,031,660	$ 10,933,977
Construction in process	899,302	1,073,402
Land held for future development	266,834	757,556
Less: accumulated depreciation	(2,558,620)	(2,323,818)
Total real estate	10,639,176	10,441,117
Cash and cash equivalents	1,063,024	478,948
Cash held in escrows	36,759	308,031
Investments in securities	9,312	8,732
Tenant and other receivables (net of allowance for doubtful accounts of $1,650 and $2,081, respectively)	47,554	60,813
Related party notes receivable	276,375	270,000
Interest receivable from related party note receivable	84,782	69,005
Accrued rental income (net of allowance of $2,356 and $3,116, respectively)	508,838	442,683
Deferred charges, net	441,700	436,019
Prepaid expenses and other assets	102,812	65,663
Investments in unconsolidated joint ventures	770,466	767,252
Total assets	13,980,798	13,348,263
Liabilities:
Mortgage notes payable	3,179,034	3,047,586
Unsecured senior notes (net of discount of $8,014 and $8,402, respectively)	3,016,986	3,016,598
Unsecured exchangeable senior notes (net of discount of $4,699 and $8,249, respectively)	1,754,343	1,721,817
Unsecured line of credit
Accounts payable and accrued expenses	172,928	186,059
Dividends and distributions payable	83,584	81,031
Accrued interest payable	89,555	62,327
Other liabilities	244,555	213,000
Total liabilities	8,540,985	8,328,418
Commitments and contingencies
Noncontrolling interest:
Redeemable preferred units of the Operating Partnership	55,652	55,652
Equity:
Excess stock, $.01 par value, 150,000,000 shares authorized, none issued or outstanding
Preferred stock, $.01 par value, 50,000,000 shares authorized, none issued or outstanding
Common stock, $.01 par value, 250,000,000 shares authorized, 147,706,147 and 140,278,005 issued and 147,627,247 and 140,199,105 outstanding at September 30, 2011 and December 31, 2010, respectively	1,476	1,402
Additional paid-in capital	4,916,440	4,417,162
Dividends in excess of earnings	(72,941)	(24,763)
Treasury common stock at cost, 78,900 shares at September 30, 2011 and December 31, 2010	(2,722)	(2,722)
Accumulated other comprehensive loss	(16,717)	(18,436)
Total stockholders' equity attributable to Boston Properties, Inc.	4,825,536	4,372,643
Noncontrolling interests:
Common units of the Operating Partnership	559,621	592,164
Property partnerships	(996)	(614)
Total equity	5,384,161	4,964,193
Total liabilities and equity	$ 13,980,798	$ 13,348,263