Net Income per Share

6 Months Ended

Jun. 30, 2011

Earnings Per Share Reconciliation [Abstract]

Net Income per Share

Net Income per Share

Basic net income per share is computed using the weighted average number of common shares outstanding during the applicable period. Diluted net income per share is computed using the weighted average number of common shares outstanding during the period, plus the dilutive effect of potential common stock. Potential common stock consists of shares issuable pursuant to stock options, deferred stock units, restricted stock units (“RSUs”) and convertible notes.

The following table sets forth the components used in the computation of basic and diluted net income per common share (in thousands, except per share data):

	For the Three Months Ended June 30,				For the Six Months Ended June 30,
	2011		2010		2011		2010
Numerator:
Net income	$	47,921	$	38,123	$	98,538	$	79,001
Add back of interest expense on 1% convertible senior notes (net of tax)	—		396		—		818
Numerator for diluted net income per common share	$	47,921	$	38,519	$	98,538	$	79,819
Denominator:
Denominator for basic net income per common share	186,612		173,317		186,731		172,209
Effect of dilutive securities:
Stock options	2,810		3,992		3,081		3,717
Effect of escrow contingencies	—		339		—		339
RSUs and deferred stock units	757		1,396		969		1,299
Assumed conversion of 1% convertible senior notes	—		11,435		—		12,182
Denominator for diluted net income per common share	190,179		190,479		190,781		189,746
Basic net income per common share	$	0.26	$	0.22	$	0.53	$	0.46
Diluted net income per common share	$	0.25	$	0.20	$	0.52	$	0.42

Outstanding options to acquire an aggregate of 2.5 million and 1.1 million shares of common stock for the three months ended June 30, 2011 and 2010, respectively, were excluded from the calculation of diluted earnings per share because the exercise prices of these stock options were greater than the average market price of the Company’s common stock during the respective periods. As a result, the effect of including these options would be anti-dilutive. Similarly, outstanding options to acquire an aggregate of 2.1 million and 1.6 million shares of common stock for the six months ended June 30, 2011 and 2010, respectively, were excluded from the calculation of diluted earnings per share because the exercise prices of the stock options were greater than the average market price of the Company's common stock during the respective periods. Additionally, 2.9 million and 3.0 million shares of common stock issuable in respect of outstanding performance-based RSUs were excluded from the computation of diluted net income per share for the three and six months ended June 30, 2011, respectively, and 3.2 million and 3.3 million shares of common stock issuable in respect of outstanding performance-based RSUs were excluded from the computation of diluted net income per share for the three and six months ended June 30, 2010, respectively, because the performance conditions had not been met as of those dates.

The calculation of assumed proceeds used to determine the diluted weighted average shares outstanding under the treasury stock method in the periods presented was adjusted by tax windfalls and shortfalls associated with all of the Company’s outstanding stock awards. Such windfalls and shortfalls are computed by comparing the tax deductible amount of outstanding stock awards to their grant date fair values and multiplying the results by the applicable statutory tax rate. A positive result creates a windfall, which increases the assumed proceeds, and a negative result creates a shortfall, which reduces the assumed proceeds.