Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

STOCK-BASED COMPENSATION (Details) (USD $)	3 Months Ended								3 Months Ended		3 Months Ended
STOCK-BASED COMPENSATION (Details) (USD $)	Mar. 31, 2012	Mar. 31, 2012 Stock Options anniversary Y	Mar. 31, 2012 Restricted Stock, Restricted Stock Units and Cash Settled Restricted Stock Units anniversary	Mar. 31, 2012 Partnership Phantom Units	May 31, 2011 Stock Incentive Plan	Aug. 31, 2007 Stock Incentive Plan	Mar. 31, 2012 Stock Incentive Plan Stock Options	Mar. 31, 2012 Stock Incentive Plan Restricted Stock, Restricted Stock Units and Cash Settled Restricted Stock Units	Mar. 31, 2012 Employee Stock Purchase Plan	May 31, 2011 Employee Stock Purchase Plan	Mar. 31, 2012 Employee Stock Purchase Plan Minimum	Mar. 31, 2012 Employee Stock Purchase Plan Maximum
Stock-based compensation
Number of shares authorized and reserved for issuance				1,035,378	12,500,000	9,750,000				1,000,000
Number of shares counted by each award							1	2
Expiration period (in years)		7 years
Vesting of awards per anniversary or year (as a percent)		33.33%	33.33%
Number of anniversaries of grant date on which awards will vest		3	3
Weighted average fair value at date of grant (in dollars per share)		$ 5.74
Weighted average assumptions
Expected life in years		4.5
Risk-free interest rate (as a percent)		0.78%
Volatility (as a percent)		47.96%
Dividend yield (as a percent)		0.00%
Stock Options
Options outstanding at the beginning of the period (in shares)		3,271,000
Granted (in shares)		153,000
Cancelled (in shares)		(365,000)
Options outstanding at the end of the period (in shares)		3,059,000
Options exercisable at the end of the period (in shares)		2,056,000
Weighted Average Exercise Price
Options outstanding at the beginning of the period (in dollars per share)		$ 27.39
Granted (in dollars per share)		$ 14.36
Cancelled (in dollars per share)		$ 22.65
Options outstanding at end of period, (in dollars per share)		$ 27.30
Options exercisable at the end of period (in dollars per share)		$ 33.38
Weighted Average Remaining Life
Outstanding at the end of the period (in years)		4 years 11 months
Exercisable at the end of the period (in years)		3 years 6 months
Aggregate Intrinsic Value
Outstanding at the end of the period		$ 1,637,000
Unrecognized compensation
Unrecognized compensation cost related to unvested stock options		4,700,000
Unrecognized compensation cost is expected to be recognized over a weighted average period (in years)		2 years 4 months	2 years 6 months	2 years 5 months
Shares
Non-vested awards at the beginning of the period (in shares)			1,670,000	75,267,000
Granted (in shares)			1,212,000	17,814,000
Vested (in shares)			(598,000)	(29,950,000)
Cancelled (in shares)			(50,000)
Non-vested awards at the end of the period (in shares)			2,234,000	63,131,000
Weighted Average Grant-Date Fair Value Per Share
Non-vested awards at the beginning of the period (in dollars per share)			$ 19.49	$ 21.45
Granted (in dollars per share)			$ 14.31	$ 23.70
Vested (in dollars per share)			$ 20.54	$ 17.53
Cancelled (in dollars per share)			$ 22.02
Non-vested awards at the end of the period (in dollars per share)			$ 16.34	$ 23.94
Unrecognized compensation cost related to unvested restricted stock and restricted stock units			31,800,000	1,300,000
Aggregate Share Based Compensation Disclosures
Minimum number of full trading days	2 days
Employee stock purchase plan
Amount for Employee stock purchase plan									$ 25,000
Percentage of Employee stock purchase plan									10.00%
Purchase price as a percent of the fair market value											85.00%	100.00%
Shares remained available for purchase under ESPP									437,332
Employee Stock Purchase plan discount from market price (as a percent)									5.00%