STOCK-BASED COMPENSATION (Details) (USD $)				12 Months Ended				12 Months Ended														12 Months Ended
	Dec. 31, 2012	Dec. 31, 2010	May 13, 2010	Dec. 31, 2012 2010 Omnibus Incentive Plan	Dec. 31, 2010 2010 Omnibus Incentive Plan	May 13, 2010 2010 Omnibus Incentive Plan	May 13, 2010 2002 Stock Incentive and Bonus Plan and 2003 Non-Employee Directors' Stock Incentive Plan	Dec. 31, 2012 Restricted Stock Units Y	Dec. 31, 2011 Restricted Stock Units	Dec. 31, 2010 Restricted Stock Units	Dec. 31, 2012 Restricted Stock Units Employee Awards	Dec. 31, 2011 Restricted Stock Units Employee Awards	Dec. 31, 2010 Restricted Stock Units Employee Awards	Dec. 31, 2012 Restricted Stock Units Director Awards	Dec. 31, 2011 Restricted Stock Units Director Awards	Dec. 31, 2010 Restricted Stock Units Director Awards	Dec. 31, 2012 Stock options Y	Dec. 31, 2011 Stock options Y	Dec. 31, 2012 Stock options Employee Awards Y	Dec. 31, 2010 Stock options Employee Awards	Dec. 31, 2011 Stock options Employee Awards	Dec. 31, 2012 Stock options Director Awards Y	Dec. 31, 2011 Stock options Director Awards	Dec. 31, 2010 Stock options Director Awards	Dec. 31, 2011 Stock options Non-Qualified Awards	Dec. 31, 2010 Stock options Non-Qualified Awards
Stock Based Compensation
Shares of common stock authorized for issuance under the share-based compensation plan			2,500,000			2,000,000	500,000
Shares of common stock authorized for issuance pursuant to the exercise of incentive stock options		1,500,000
Plan expiration unless earlier terminated by the Board of Directors					10 years
Shares of common stock issued under the Plan				1,200,000
Number of authorized shares canceled	200,000
Number of shares of available for future issuance	1,500,000
Unrecognized share-based compensation cost related to unvested stock								$ 12,700,000
Period over which unrecognized share-based compensation cost will be expensed								4 years
Share- based compensation cost								8,100,000	8,100,000	7,500,000
The weighted average period over which unrecognized share-based compensation cost will be expensed (in years)								2
Shares
Nonvested at the beginning of the period (in shares)											893,523	808,071	986,461	115,918	133,754	129,123
Granted (in shares)											468,500	487,620	454,950	63,497	59,698	75,710
Shares fully vested								376,986	436,600		318,927	374,067	585,228	58,059	62,533	71,079
Forfeited (in shares)											(231,537)	(28,101)	(48,112)		(15,001)
Nonvested at the end of the period (in shares)											811,559	893,523	808,071	121,356	115,918	133,754
Intrinsic value of options exercised																	3,600,000	2,700,000
Options exercisable (in shares)																	200,000	500,000
Weighted average exercise price of options exercisable (in dollars per share)																	$ 11.72	$ 13.36
Average remaining contractual term of options exercisable (in years)																	1.0	1.7
Aggregate intrinsic value of exercisable options																	2,600,000	6,200,000
Cash received related to exercise of options																	3,600,000	2,700,000
Weighted Average Grant Date Fair Value
Nonvested at the beginning of the period (in dollars per share)											$ 21.84	$ 16.33	$ 12.29	$ 21.12	$ 16.38	$ 13.21
Granted (in dollars per share)											$ 20.47	$ 25.25	$ 18.45	$ 22.35	$ 25.72	$ 18.48
Vested (in dollars per share)											$ 20.17	$ 14.61	$ 11.36	$ 19.34	$ 15.46	$ 12.86
Forfeited (in dollars per share)											$ 21.26	$ 19.17	$ 13.99		$ 20.80
Nonvested at the end of the period (in dollars per share)											$ 21.76	$ 21.84	$ 16.33	$ 22.62	$ 21.12	$ 16.38
Intrinsic value of shares fully vested during the period								7,600,000	6,400,000
Value of grants during the period								11,000,000	13,300,000
Shares
Outstanding at the beginning of the period (in shares)																			434,500	764,332		28,259	80,091	95,464	376,000	406,000
Terminated (in shares)																			(1,500)	(1,500)			(10,373)
Exercised (in shares)																			(230,000)	(328,332)		(9,404)	(41,459)	(15,373)	(376,000)	(30,000)
Outstanding at the end of the period (in shares)																			203,000	434,500		18,855	28,259	80,091		376,000
Weighted Average Exercise Price
Outstanding at the beginning of the period (in dollars per share)																			$ 13.45	$ 13.74		$ 11.99	$ 11.08	$ 11.46	$ 5.98	$ 5.95
Terminated (in dollars per share)																			$ 15.60	$ 4.63			$ 10.79
Exercised (in dollars per share)																			$ 14.82	$ 14.16		$ 16.04	$ 10.38	$ 13.82	$ 5.98	$ 5.50
Outstanding at the end of the period (in dollars per share)																			$ 11.88	$ 13.45		$ 10.02	$ 11.99	$ 11.08		$ 5.98
Aggregate intrinsic value																			$ 2,411,300			$ 189,003
Weighted average remaining contractual term (in years)																			1.0			1.0
Summary of options vested and exercisable
Options vested and exercisable (in shares)																			203,000	434,500	434,500	18,855	28,259	80,091		376,000