STOCK-BASED COMPENSATION (Details) (USD $)	12 Months Ended
	Dec. 31, 2011 Y	Dec. 31, 2010	Dec. 31, 2009	May 17, 2011
Stock-based compensation
Maximum shares of common stock that can be issued under the 2011 plan				1,800,000
Shares available for future grant to employees and non-employee directors under the 2009 Plan	1,685,044
Total after-tax share-based compensation cost by type of program
Before-tax share-based compensation expense	$ 6,658,000	$ 3,487,000	$ 17,661,000
Income tax benefit	(1,755,000)	(943,000)	(6,245,000)
After-tax share-based compensation expense	4,903,000	2,544,000	11,416,000
Weighted average recognition period of total unrecognized compensation cost (in years)	2
Total unrecognized compensation cost related to nonvested share-based compensation	6,300,000
Total fair value of shares vested	5,300,000	7,000,000	13,800,000
Restricted and deferred stock units
Total after-tax share-based compensation cost by type of program
Before-tax share-based compensation expense	6,433,000	2,784,000	16,164,000
Stock Options
Total after-tax share-based compensation cost by type of program
Before-tax share-based compensation expense	$ 225,000	$ 703,000	$ 1,497,000