Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
ASSETS
Real estate, at cost	$ 17,258,665	$ 17,158,210
Construction in progress	1,564,821	1,523,179
Land held for future development	300,498	297,376
Less: accumulated depreciation	(3,263,208)	(3,161,571)
Total real estate	15,860,776	15,817,194
Cash and cash equivalents	1,179,573	2,365,137
Cash held in escrows	54,240	57,201
Investments in securities	18,026	16,641
Tenant and other receivables (net of allowance for doubtful accounts of $1,625 and $1,636, respectively)	37,812	59,464
Accrued rental income (net of allowance of $3,448 and $3,636, respectively	661,730	651,603
Deferred charges, net	861,567	884,450
Prepaid expenses and other assets	178,488	184,477
Investments in unconsolidated joint ventures	127,356	126,084
Total assets	18,979,568	20,162,251
Liabilities:
Mortgage notes payable	4,430,110	4,449,734
Unsecured senior notes (net of discount of $13,710 and $14,146 respectively)	5,836,290	5,835,854
Unsecured exchangeable senior notes (net of discount of $0 and $182, respectively	0	744,880
Unsecured line of credit	0	0
Mezzanine notes payable	310,735	311,040
Outside member's notes payable	180,000	180,000
Accounts payable and accrued expenses	218,028	202,470
Dividends and distributions payable	114,799	497,242
Accrued interest payable	178,651	167,523
Other liabilities	556,772	578,969
Total liabilities	11,825,385	12,967,712
Commitments and contingencies	0	0
Noncontrolling interest:
Redeemable preferred units of the Operating Partnership	51,312	51,312
Redeemable interest in property partnerships	100,327	99,609
Equity:
Excess stock, $.01 par value, 150,000,000 shares authorized, none issued or outstanding	0	0
Preferred stock, $.01 par value, 50,000,000 shares authorized
5.25% Series B cumulative redeemable preferred stock, $.01 par value, liquidation preference of $2,500 per share, 92,000 shares authorized, 80,000 shares issued and outstanding at March 31, 2014 and December 31,2013	200,000	200,000
Common stock, $.01 par value, 250,000,000 shares authorized, 153,096,211 and 153,062,001 issued and 153,017,311 and 152,983,101 outstanding at March 31, 2014 and December 31, 2013, respectively	1,530	1,530
Additional paid-in capital	5,668,230	5,662,453
Dividends in excess of earnings	(153,979)	(108,552)
Treasury common stock at cost, 78,900 shares at March 31, 2014 and December 31, 2013	(2,722)	(2,722)
Accumulated other comprehensive loss	(10,989)	(11,556)
Total stockholders' equity attributable to Boston Properties, Inc.	5,702,070	5,741,153
Noncontrolling interests:
Common units of the Operating Partnership	575,381	576,333
Property partnerships	725,093	726,132
Total equity	7,002,544	7,043,618
Total liabilities and equity	$ 18,979,568	$ 20,162,251