Real Estate (Summary Of The Discontinued Operations Related To Bedford Business Park) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total revenue	$ 1,876,267	$ 1,751,320	$ 1,543,310
Expenses
Depreciation and amortization	453,068	436,612	335,859
Total expenses	1,224,586	1,134,561	934,238
Noncontrolling interest in income (loss) from discontinued operations - common units of the Operating Partnership	(4,154)	(215)	(184)
Income from discontinued operations attributable to Boston Properties, Inc.	33,763	1,666	1,258
Gain on sale of real estate from discontinued operations	36,877	0	0
Bedford Business Park [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total revenue	3,526	8,206	7,494
Expenses
Operating	1,510	3,753	3,540
Depreciation and amortization	976	2,572	2,512
Total expenses	2,486	6,325	6,052
Income from discontinued operations	1,040	1,881	1,442
Noncontrolling interest in income (loss) from discontinued operations - common units of the Operating Partnership	(109)	(215)	(184)
Income from discontinued operations attributable to Boston Properties, Inc.	931	1,666	1,258
Gain on sale of real estate from discontinued operations	36,877	0	0
Noncontrolling interest in gain on sale of real estate from discontinued operations - common units of the Operating Partnership	(4,045)	0	0
Gain on sale of real estate from discontinued operations attributable to Boston Properties, Inc	$ 32,832	$ 0