ORGANIZATION AND ACCOUNTING POLICIES (Details 4) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
ORGANIZATION AND ACCOUNTING POLICIES
Weighted average shares outstanding - basic	71,376,046	70,830,855	70,382,517
Incremental shares issuable from dilutive stock options	720,626	1,216,633	1,046,593
Weighted average shares outstanding - diluted	72,096,672	72,047,488	71,429,110
Employee stock options
Antidilutive securities
Anti-dilutive securities (in shares)	575,750	918,416	2,208,666
Convertible debentures
Antidilutive securities
Anti-dilutive securities (in shares)	32,720	47,170	47,170
Percentage of principal amount at which debentures may be converted from the date of issuance until maturity into common stock	100.00%	100.00%	100.00%
Conversion price (in dollars per share)	50.00
Convertible debentures | Minimum
Antidilutive securities
Conversion price (in dollars per share)		35.00	35.00
Convertible debentures | Maximum
Antidilutive securities
Conversion price (in dollars per share)		50.00	50.00
Preferred stock
Antidilutive securities
Anti-dilutive securities (in shares)	5,352	5,352	5,352
Percentage of redemption price amount from the date of issuance until redemption that may be converted	100.00%
Preferred stock | Minimum
Antidilutive securities
Conversion rate (in shares)	0.5
Preferred stock | Maximum
Antidilutive securities
Conversion rate (in shares)	1
Restricted Stock
Antidilutive securities
Anti-dilutive securities (in shares)	1,606,460	615,731	28,373