Net Income (Loss) Per Common Share

3 Months Ended

Mar. 31, 2013

Earnings Per Share [Abstract]

Net Income (Loss) Per Common Share

Net Income (Loss) Per Common Share or Common Unit

Basic net income (loss) per common share or Common Unit is computed by dividing net income (loss) attributable to common shareholders or common unitholders, less dividends or distributions on share-based awards expected to vest (referred to as "participating securities" and primarily composed of unvested restricted stock units), by the weighted average number of common shares or Common Units outstanding for the period.

Diluted net income (loss) per common share is computed by dividing the sum of basic net income (loss) attributable to common shareholders and the noncontrolling interest in earnings allocable to Limited Partner Units (to the extent the Limited Partner Units are dilutive) by the sum of the weighted average number of common shares outstanding and, to the extent they are dilutive, Units outstanding and any potential dilutive securities for the period. Diluted net income (loss) per Common Unit is computed by dividing the basic net income (loss) attributable to common unitholders by the sum of the weighted average number of Common Units outstanding and any potential dilutive securities for the period.

The following table reconciles the components of basic and diluted net income (loss) per common share or Common Unit for the three months ended March 31,2013 and 2012, respectively (in thousands): 

	Three Months Ended March 31,
	2013			2012
General Partner
Net income (loss) attributable to common shareholders	$	28,043		$	(36,390	)
Less: Dividends on participating securities	(688		)	(852		)
Basic net income (loss) attributable to common shareholders	27,355			(37,242		)
Noncontrolling interest in earnings of common unitholders	392			—
Diluted net income (loss) attributable to common shareholders	$	27,747		$	(37,242	)
Weighted average number of common shares outstanding	314,936			258,365
Weighted average Limited Partner Units outstanding	4,405			—
Other potential dilutive shares	230			—
Weighted average number of common shares and potential dilutive securities	319,571			258,365
Partnership
Net income (loss) attributable to common unitholders	$	28,435		$	(37,201	)
Less: Distributions on participating securities	(688		)	(852		)
Basic and diluted net income (loss) attributable to common unitholders	$	27,747		$	(38,053	)
Weighted average number of Common Units outstanding	319,341			264,114
Other potential dilutive units	230			—
Weighted average number of Common Units and potential dilutive securities	319,571			264,114

The Limited Partner Units are anti-dilutive to the General Partner for the three months ended March 31, 2012 as a result of the net loss for that period. In addition, substantially all potential shares related to our stock-based compensation plans are anti-dilutive for all periods presented. The following table summarizes the data that is excluded from the computation of net income (loss) per common share or Common Unit as a result of being anti-dilutive (in thousands):

	Three Months Ended March 31,
	2013		2012
General Partner
Noncontrolling interest in loss of common unitholders	$	—	$	(811	)
Weighted average Limited Partner Units outstanding	—		5,749
General Partner and Partnership
Other potential dilutive shares or units:
Anti-dilutive outstanding potential shares or units under fixed stock option and other stock-based compensation plans	1,378		1,733
Outstanding participating securities	4,078		5,051