NET INCOME PER SHARE (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Reconciliation of the numerator and denominator of basic and diluted net income per share
Net income	$ 21,636	$ 116,706	$ 42,777	$ 282,129
Weighted-average shares - basic	430,845	457,721	434,894	456,992
Dilutive effect of incremental shares and share equivalents	2,450	9,141	3,338	10,048
Weighted-average shares - diluted	433,295	466,862	438,232	467,040
Basic
Net income per share (in dollars per share)	$ 0.05	$ 0.25	$ 0.10	$ 0.62
Diluted
Net income per share (in dollars per share)	$ 0.05	$ 0.25	$ 0.10	$ 0.60
Anti-dilutive securities not included in the "Weighted-average shares - diluted" used for calculation of diluted net income per share
Employee stock options and restricted stock units outstanding (in shares)	9,991	1,999	7,739	1,030