Earnings Per Share (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Basic Earnings:
Income from continuing operations attributable to Boston Properties, Inc., Income (Numerator)	$ 255,887	$ 271,013	$ 157,814
Net income attributable to Boston Properties Inc., Shares (Denominator)	150,120	145,693	139,440
Income from continuing operations attributable to Boston Properties, Inc., Per Share Amount (in dollars per share)	$ 1.71	$ 1.86	$ 1.13
Discontinued operations attributable to Boston Properties, Inc., Income (Numerator)	33,763	1,666	1,258
Discontinued operations attributable to Boston Properties, Inc., Per Share Amount (in dollars per share)	$ 0.22	$ 0.01	$ 0.01
Net income attributable to Boston Properties, Inc.	289,650	272,679	159,072
Net income attributable to Boston Properties Inc., Per Share Amount (in dollars per share)	$ 1.93	$ 1.87	$ 1.14
Effect of Dilutive Securities:
Stock Based Compensation and Exchangeable Senior Notes, Income (Numerator)	0	0	0
Stock Based Compensation and Exchangeable Senior Notes, Shares (Denominator)	591	525	617
Stock Based Compensation and Exchangeable Senior Notes Per Share Amount	$ (0.01)	$ (0.01)	$ 0.00
Diluted Earnings:
Diluted Earnings: Net income, Income (Numerator)	$ 289,650	$ 272,679	$ 159,072
Diluted Earnings: Net income, Shares (Denominator)	150,711	146,218	140,057
Diluted Earnings: Net income, Per Share Amount (in dollars per share)	$ 1.92	$ 1.86	$ 1.14