CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010
CONSOLIDATED BALANCE SHEETS
Common stock, par value (in dollars per share)	$ 0.005	$ 0.005
Common stock, shares authorized	240,000	240,000
Common stock, shares issued	198,729	197,462
Common stock, shares outstanding	174,277	177,960
Common stock in treasury, shares	24,452	19,502
Ratio for Numerator of Common Stock Issued for Stock Split	2	2
Ratio for Denominator of Common Stock Issued for Stock Split	1	1
Stock Dividend Rate (as a Percentage)	100.00%	100.00%