EARNINGS PER SHARE (NVE) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended												12 Months Ended
	Dec. 31, 2012		Sep. 30, 2012		Jun. 30, 2012		Mar. 31, 2012		Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Numerator
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	$ 17,164		$ 223,170		$ 69,439		$ 12,173		$ (25,248)	$ 173,462	$ 12,888	$ 2,330	$ 321,946		$ 163,432		$ 226,984
Denominator
Weighted Average Shares of Common Stock Outstanding - basic													235,840,558		235,847,596		235,048,347
Per Share Amounts
Net income per share - basic	$ 0.07	[1]	$ 0.95	[1]	$ 0.29	[1]	$ 0.05	[1]	$ (0.11)	$ 0.74	$ 0.05	$ 0.01	$ 1.37		$ 0.69		$ 0.97
Numerator
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	$ 17,164		$ 223,170		$ 69,439		$ 12,173		$ (25,248)	$ 173,462	$ 12,888	$ 2,330	$ 321,946		$ 163,432		$ 226,984
Denominator
Weighted Average Number of Shares Outstanding, Basic													235,840,558		235,847,596		235,048,347
Stock options (in shares)													31,443		36,189		34,590
Non-Employee Director stock plan (in shares)													163,543		143,791		141,577
Employee stock purchase plan (in shares)													5,671		4,111		5,909
Restricted Shares (in shares)													545,750		395,813		78,920
Performance Shares (in shares)													1,296,916		1,339,571		985,469
Weighted Average Number of Shares Outstanding, Diluted													237,883,881	[2]	237,767,071	[2]	236,294,812	[2]
Per Share Amounts
Net income per share - diluted	$ 0.07		$ 0.94		$ 0.29		$ 0.05		$ (0.11)	$ 0.73	$ 0.05	$ 0.01	$ 1.35		$ 0.69		$ 0.96
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount													297,803		390,095		563,624

[1] Total Net Income per Share per the Consolidated Statement of Comprehensive Income may differ slightly due to rounding.

[2] 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. Under this plan, an additional 297,803, 390,095 and 563,624 shares for 2012, 2011 and 2010, respectively, would be included in each of these periods if the conditions for conversion were met.