Segment Information (Schedule Of Reconciliation Of Net Operating Income To Net Income) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Development and management services income	$ 34,077	$ 33,425	$ 41,215
Income from unconsolidated joint ventures	49,078	85,896	36,774
Interest and other income	10,091	5,358	7,332
Gains (losses) from investments in securities	1,389	(443)	935
Gains on sales of real estate	0	0	2,734
Income from discontinued operations	1,040	1,881	1,442
Gain on sale of real estate from discontinued operations	36,877	0	0
General and administrative expense	82,382	79,610	79,396
Transaction costs	3,653	1,987	2,876
Suspension of development	0	0	(7,200)
Depreciation and amortization expense	453,068	436,612	335,859
Interest expense	413,564	394,131	378,079
Losses from early extinguishments of debt	4,453	1,494	89,883
Noncontrolling interest in property partnerships	3,792	1,558	3,464
Noncontrolling interest-redeemable preferred units of the Operating Partnership	3,497	3,339	3,343
Noncontrolling interest-common units of the Operating Partnership	31,046	36,035	23,915
Noncontrolling interest In gains on sales Of real estate common units of the operating partnership	0	0	(349)
Noncontrolling interest in discontinued operations-common units of the Operating Partnership	4,154	215	184
Net income attributable to Boston Properties, Inc.	289,650	272,679	159,072
Business Intersegment, Eliminations [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net Operating Income	1,156,707	1,101,543	978,788
Development and management services income	34,077	33,425	41,215
Income from unconsolidated joint ventures	49,078	85,896	36,774
Interest and other income	10,091	5,358	7,332
Gains (losses) from investments in securities	1,389	(443)	935
Gains on sales of real estate	0	0	2,734
Income from discontinued operations	1,040	1,881	1,442
Gain on sale of real estate from discontinued operations	36,877	0	0
General and administrative expense	82,382	79,610	79,396
Transaction costs	3,653	1,987	2,876
Suspension of development	0	0	(7,200)
Depreciation and amortization expense	453,068	436,612	335,859
Interest expense	413,564	394,131	378,079
Losses from early extinguishments of debt	4,453	1,494	89,883
Noncontrolling interest in property partnerships	3,792	1,558	3,464
Noncontrolling interest-redeemable preferred units of the Operating Partnership	3,497	3,339	3,343
Noncontrolling interest-common units of the Operating Partnership	31,046	36,035	23,915
Noncontrolling interest In gains on sales Of real estate common units of the operating partnership	0	0	(349)
Noncontrolling interest in discontinued operations-common units of the Operating Partnership	4,154	215	184
Net income attributable to Boston Properties, Inc.	$ 289,650	$ 272,679	$ 159,072