EARNINGS PER SHARE (NVE) (Details) (USD $) In Thousands, except Share data	3 Months Ended				6 Months Ended
	Jun. 30, 2011		Jun. 30, 2010		Jun. 30, 2011		Jun. 30, 2010
Numerator
Net income	$ 12,888		$ 36,946		$ 15,218		$ 35,225
Denominator
Weighted average number of common shares outstanding (in shares)	235,867,068		234,995,083		235,697,687		234,927,239
Per Share Amounts
Net income per share - basic (in dollars per share)	$ 0.05		$ 0.16		$ 0.06		$ 0.15
Numerator
Net Income (Loss)	$ 12,888		$ 36,946		$ 15,218		$ 35,225
Denominator
Weighted average number of common shares outstanding (in shares)	235,867,068		234,995,083		235,697,687		234,927,239
Stock options	42,199		29,132		37,799		28,241
Non-Employee Director stock plan (in shares)	122,737		135,436		143,319		131,690
Employee stock purchase plan (in shares)	2,528		3,538		3,551		4,548
Restricted Shares (in shares)	124,116		66,062		112,678		60,177
Performance Shares (in shares)	1,119,898		905,198		1,032,622		813,557
Weighted average number of shares outstanding after dilution (in shares)	237,278,546	[1]	236,134,449	[1]	237,027,656	[1]	235,965,452	[1]
Per Share Amounts
Net income per share - diluted (in dollars per share)	$ 0.05		$ 0.16		$ 0.06		$ 0.15
Excluded stock equivalents for options issued under the non-qualified stock option plan (in shares)	572,957		708,031		577,357		711,330

[1] The denominator does not include stock equivalents for options issued under the non-qualified stock option plan due to conversion prices being higher than market prices for all periods. If the conditions for conversion were met under this plan, 572,957 and 577,357 shares would be included for the three and six months ended June 30, 2011, and 708,031 and 711,330 would be included for the three and six months ended June 30, 2010, respectively.