NET INCOME (LOSS) PER SHARE (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Reconciliation of the numerator and denominator of basic and diluted net income (loss) per share
Net income (loss)	$ 314,990	$ 423,075	$ (109,498)
Weighted-average shares - basic	455,629	458,482	451,755
Incremental shares and share equivalents	7,044	11,098
Weighted-average shares - diluted	462,673	469,580	451,755
Net income (loss) per share:
Net income (loss) per share - basic (in dollars per share)	$ 0.69	$ 0.92	$ (0.24)
Net income (loss) per share - diluted (in dollars per share)	$ 0.68	$ 0.90	$ (0.24)
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)	1,977	2,095	51,788