Earnings Per Share

3 Months Ended

Mar. 31, 2012

Earnings Per Share [Abstract]

Earnings Per Share

10. Earnings Per Share

The following table provides a reconciliation of both the net income attributable to Boston Properties, Inc. and the number of common shares used in the computation of basic earnings per share ("EPS"), which is calculated by dividing net income attributable to Boston Properties, Inc. by the weighted-average number of common shares outstanding during the period. The terms of the Series Two Preferred Units enable the holders to obtain OP Units of the Operating Partnership, as well as Common Stock of the Company. As a result, the Series Two Preferred Units are considered participating securities and are included in the computation of basic and diluted earnings per share of the Company if the effect of applying the if-converted method is dilutive. Unvested share-based payment awards that contain non-forfeitable rights to dividends or dividend equivalents (whether paid or unpaid) are participating securities and shall be included in the computation of EPS pursuant to the two-class method. As a result, unvested restricted common stock of the Company, LTIP Units and OPP Units are considered participating securities and are included in the computation of basic and diluted earnings per share of the Company if the effect of applying the if-converted method is dilutive. Because the OPP Units require the Company to outperform absolute and relative return thresholds, unless such thresholds have been met by the end of the applicable reporting period, the Company excludes such units from the diluted EPS calculation. For the three months ended March 31, 2012, assuming the measurement period for the 2011 OPP Units ended on March 31, 2012, the Company's total return to stockholders compared to the absolute and relative return thresholds for the 2011 OPP Units would have resulted in participants earning and being eligible to vest in an aggregate of approximately 129,000 2011 OPP Units. As a result, these 2011 OPP Units have been included in the diluted EPS calculation. For the three months ended March 31, 2012, the absolute and relative return thresholds for the 2012 OPP Units were not met and as a result the 2012 OPP Units have been excluded from the diluted EPS calculation. For the three months ended March 31, 2011, the absolute and relative return thresholds for the 2008 OPP Units and 2011 OPP Units were not met and as a result the 2008 OPP Units and 2011 OPP Units have been excluded from the diluted EPS calculation. Other potentially dilutive common shares, including stock options, restricted stock and other securities of the Operating Partnership that are exchangeable for the Company's Common Stock, and the related impact on earnings, are considered when calculating diluted EPS.

	For the three months ended March 31, 2012
	Income (Numerator)		Shares (Denominator)		Per Share Amount
	(in thousands, except for per share amounts)
Basic Earnings:
Income from continuing operations attributable to Boston Properties, Inc.	$	48,923		148,343	$	0.33
Discontinued operations attributable to Boston Properties, Inc.		15,709		—		0.11
Net income attributable to Boston Properties, Inc.	$	64,632		148,343	$	0.44
Effect of Dilutive Securities:
Stock Based Compensation and Exchangeable Senior Notes		—		403		(0.01	)
Diluted Earnings:
Net income	$	64,632		148,746	$	0.43

	For the three months ended March 31, 2011
	Income (Numerator)			Shares (Denominator)		Per Share Amount
	(in thousands, except for per share amounts)
Basic Earnings:
Income from continuing operations attributable to Boston Properties, Inc.	$	41,249			142,095	$	0.29
Discontinued operations attributable to Boston Properties, Inc.		(436	)		—		(0.00	)
Net income attributable to Boston Properties, Inc.	$	40,813			142,095	$	0.29
Effect of Dilutive Securities:
Stock Based Compensation and Exchangeable Senior Notes		—			409		(0.00	)
Diluted Earnings:
Net income	$	40,813			142,504	$	0.29