STOCK-BASED COMPENSATION (Details) (USD $)	3 Months Ended		93 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013
Weighted Average Grant Price [Roll Forward]
Stock compensation expense	$ 724,000	$ 431,000
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights	The shares of restricted stock granted to employees and that are outstanding as of March 31, 2013 vest in accordance with one of the following vesting schedules: 100% one year after date of grant; 33.3% each year for three years after date of grant; 20% each year for five years after the grant date; or 10% each year for ten years after the grant date.
Numerator used for calculating the number of whole shares granted	75,000
Award vesting period	1 year
Number of shares authorized for grants (in shares)	800,000		800,000
Number of shares granted (in shares)	(80,300)		(768,671)
Number of shares forfeited (in shares)	4,748		84,746
Number of shares available for future grants (in shares)	116,075		116,075
Weighted-average grant price of granted shares (in dollars per share)	$ 50.79		$ 22.87
Restricted Stock [Roll Forward]
Non-vested, beginning balance (in shares)	210,330
Granted (in shares)	80,300		768,671
Forfeited (in shares)	(4,748)		(84,746)
Vested (in shares)	(23,433)
Nonvested, ending balance (in shares)	262,449		262,449
Weighted Average Grant Price [Roll Forward]
Non vested, beginning balance (in dollars per share)	$ 26.85
Granted (in dollars per share)	$ 50.79		$ 22.87
Forfeitures (in dollars per share)	$ 22.07
Vested (in dollars per share)	$ 29.78
Nonvested, ending balance (in dollars per share)	$ 33.98		$ 33.98
Stock compensation expense	700,000	400,000
Related income tax benefits recognized	300,000	200,000
Unrecognized compensation expense	$ 7,900,000	$ 4,600,000	$ 7,900,000
Compensation cost not yet recognized, Period for recognition	34 months 6 days