STOCK-BASED COMPENSATION Stock Options (Details) (USD $)	3 Months Ended	12 Months Ended
	Mar. 31, 2013	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares Authorized	7,500,000
Stock Options [Member]
Shares:
Outstanding at January 1, 2013	2,219,625
Forfeited	(24,375)
Outstanding at March 31, 2013	2,195,250	2,219,625
Vested or expected to vest	2,123,869
Exercisable at March 31, 2013	1,679,622
Weighted Average Exercise Price per Share:
Outstanding at January 1, 2013	$ 31.51
Forfeited	$ 38.85
Outstanding at March 31, 2013	$ 31.43	$ 31.51
Vested or expected to vest	$ 31.72
Exercisable at March 31, 2013	$ 33.92
Weighted Average Remaining Contractual Term (years), outstanding	3 years 9 months 22 days	4 years 0 months 22 days
Weighted Average Remaining Contractual Term (years), Vested or expected to vest	3 years 8 months 27 days
Weighted Average Remaining Contractual Term (years), exercisable	3 years 3 months
Aggregate Intrinsic Value, outstanding	$ 0	$ 0
Aggregate Intrinsic Value, Vested or expected to vest	0
Aggregate Intrinsic Value, exercisable	0
Unrecognized compensation expense	4,100,000
Options that may be exchanged for restricted stock unit	1,710,500.0
Restricted Stock Units (RSUs) [Member]
Weighted Average Exercise Price per Share:
Unrecognized compensation expense	$ 2,000,000
Options that may be exchanged for restricted stock unit	845,680.00
Minimum [Member] | Restricted Stock Units (RSUs) [Member]
Weighted Average Exercise Price per Share:
Award vesting period	1 year
Maximum [Member] | Restricted Stock Units (RSUs) [Member]
Weighted Average Exercise Price per Share:
Award vesting period	4 years