Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Cash flows from operating activities:
Net income	$ 282,574	$ 333,579
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	311,124	312,623
Non-cash compensation expense	19,237	17,647
Income from unconsolidated joint ventures	(6,192)	(4,025)
Distributions of net cash flow from operations of unconsolidated joint ventures	2,905	11,399
Gains from investments in securities	(1,772)	(737)
Gains from early extinguishments of debt	(14,444)	0
Non-cash portion of interest expense	(11,979)	(19,330)
Gains on sales of real estate	(3,900)	(67,623)
Change in assets and liabilities:
Cash held in escrows	7,531	632
Tenant and other receivables, net	2,033	13,963
Accrued rental income, net	(19,348)	(5,294)
Prepaid expenses and other assets	36,223	62,752
Accounts payable and accrued expenses	(2,608)	9,236
Accrued interest payable	(158,761)	31,789
Other liabilities	(33,093)	(71,805)
Tenant leasing costs	(37,252)	(40,655)
Total adjustments	89,704	250,572
Net cash provided by operating activities	372,278	584,151
Cash flows from investing activities:
Acquisition of real estate	(15,953)	(78,000)
Construction in progress	(297,747)	(242,944)
Building and other capital improvements	(100,808)	(48,306)
Tenant improvements	(107,533)	(116,935)
Proceeds from sales of real estate	17,049	104,816
Proceeds from sales of real estate placed in escrow	(16,640)	(104,696)
Proceeds from sales of real estate released from escrow	15,844	104,696
Cash released from escrow for investing activities	9,004	6,694
Cash released from escrow for land sale contracts	0	781
Deposit on real estate	0	(25,000)
Capital contributions to unconsolidated joint ventures	(41,491)	(26,040)
Investments in securities, net	(1,195)	(658)
Net cash used in investing activities	(539,470)	(425,592)
Cash flows from financing activities:
Proceeds from mortgage notes payable	2,300,000	0
Repayments of mortgage notes payable	(1,308,708)	(222,535)
Proceeds from unsecured senior notes	0	997,080
Borrowings on unsecured line of credit	430,000	0
Repayments of unsecured line of credit	(430,000)	0
Repayments of mezzanine notes payable	(306,000)	0
Repayments of outside members’ notes payable	(70,424)	0
Payments on capital lease obligations	(486)	0
Payments on real estate financing transactions	(1,013)	(4,290)
Deposit on mortgage note payable interest rate lock	(23,200)	0
Return of deposit on mortgage note payable interest rate lock	23,200	0
Deferred financing costs	(43,635)	(8,047)
Net proceeds from equity transactions	(181)	(666)
Dividends and distributions	(263,221)	(442,901)
Contributions from noncontrolling interests in property partnerships	23,496	5,040
Distributions to noncontrolling interests in property partnerships	(27,115)	(25,914)
Net cash provided by financing activities	302,713	297,767
Net increase in cash and cash equivalents	135,521	456,326
Cash and cash equivalents, beginning of period	356,914	723,718
Cash and cash equivalents, end of period	492,435	1,180,044
Supplemental disclosures:
Cash paid for interest	388,045	217,021
Interest capitalized	26,628	19,168
Non-cash investing and financing activities:
Write off of fully depreciated real estate	(86,135)	(52,708)
Additions to real estate included in accounts payable and accrued expenses	22,994	(14,471)
Real estate acquired through capital lease	28,962	0
Outside members’ notes payable contributed to noncontrolling interests in property partnerships	109,576	0
Dividends and distributions declared but not paid	130,432	113,071
Conversions of noncontrolling interests to stockholders’ equity	16,422	2,664
Issuance of restricted securities to employees	35,945	33,711
Boston Properties Limited Partnership
Cash flows from operating activities:
Net income	287,383	339,719
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	306,892	308,652
Non-cash compensation expense	19,237	17,647
Income from unconsolidated joint ventures	(6,192)	(4,025)
Distributions of net cash flow from operations of unconsolidated joint ventures	2,905	11,399
Gains from investments in securities	(1,772)	(737)
Gains from early extinguishments of debt	(14,444)	0
Non-cash portion of interest expense	(11,979)	(19,330)
Gains on sales of real estate	(4,477)	(69,792)
Change in assets and liabilities:
Cash held in escrows	7,531	632
Tenant and other receivables, net	2,033	13,963
Accrued rental income, net	(19,348)	(5,294)
Prepaid expenses and other assets	36,223	62,752
Accounts payable and accrued expenses	(2,608)	9,236
Accrued interest payable	(158,761)	31,789
Other liabilities	(33,093)	(71,805)
Tenant leasing costs	(37,252)	(40,655)
Total adjustments	84,895	244,432
Net cash provided by operating activities	372,278	584,151
Cash flows from investing activities:
Acquisition of real estate	(15,953)	(78,000)
Construction in progress	(297,747)	(242,944)
Building and other capital improvements	(100,808)	(48,306)
Tenant improvements	(107,533)	(116,935)
Proceeds from sales of real estate	17,049	104,816
Proceeds from sales of real estate placed in escrow	(16,640)	(104,696)
Proceeds from sales of real estate released from escrow	15,844	104,696
Cash released from escrow for investing activities	9,004	6,694
Cash released from escrow for land sale contracts	0	781
Deposit on real estate	0	(25,000)
Capital contributions to unconsolidated joint ventures	(41,491)	(26,040)
Investments in securities, net	(1,195)	(658)
Net cash used in investing activities	(539,470)	(425,592)
Cash flows from financing activities:
Proceeds from mortgage notes payable	2,300,000	0
Repayments of mortgage notes payable	(1,308,708)	(222,535)
Proceeds from unsecured senior notes	0	997,080
Borrowings on unsecured line of credit	430,000	0
Repayments of unsecured line of credit	(430,000)	0
Repayments of mezzanine notes payable	(306,000)	0
Repayments of outside members’ notes payable	(70,424)	0
Payments on capital lease obligations	(486)	0
Payments on real estate financing transactions	(1,013)	(4,290)
Deposit on mortgage note payable interest rate lock	(23,200)	0
Return of deposit on mortgage note payable interest rate lock	23,200	0
Deferred financing costs	(43,635)	(8,047)
Net proceeds from equity transactions	(181)	(666)
Dividends and distributions	(263,221)	(442,901)
Contributions from noncontrolling interests in property partnerships	23,496	5,040
Distributions to noncontrolling interests in property partnerships	(27,115)	(25,914)
Net cash provided by financing activities	302,713	297,767
Net increase in cash and cash equivalents	135,521	456,326
Cash and cash equivalents, beginning of period	356,914	723,718
Cash and cash equivalents, end of period	492,435	1,180,044
Supplemental disclosures:
Cash paid for interest	388,045	217,021
Interest capitalized	26,628	19,168
Non-cash investing and financing activities:
Write off of fully depreciated real estate	(85,525)	(52,708)
Additions to real estate included in accounts payable and accrued expenses	22,994	(14,471)
Real estate acquired through capital lease	28,962	0
Outside members’ notes payable contributed to noncontrolling interests in property partnerships	109,576	0
Dividends and distributions declared but not paid	130,432	113,071
Conversions of noncontrolling interests to stockholders’ equity	16,422	2,664
Issuance of restricted securities to employees	$ 35,945	$ 33,711