INCOME TAXES (Details) (USD $)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011
INCOME TAXES
Increase in the balance of unrecognized tax benefits			$ 1,000,000
Amount of unrecognized tax benefits that would, if recognized, affect the effective tax rate	3,400,000		3,400,000		2,300,000
Reconciliation of the beginning and ending amount of unrecognized tax benefits
Balance, beginning of period			4,318,000	12,659,000	12,659,000
Additions for tax positions of prior years	8,600,000		26,925,000		106,000
Reductions of tax positions of prior years:
Changes in judgment					(8,447,000)
Balance, end of period	31,243,000		31,243,000		4,318,000
Estimated reduction in unrecognized tax benefits due to the expected closure of the appeals process in the next 12 months	16,100,000		16,100,000
Effective income tax rate (as a percent)	30.30%	34.60%	31.20%	34.70%
Income tax benefit due to change in estimate	3,000,000
Income tax benefit	3,400,000
Effective tax rate without considering benefit due to change in estimate (as a percent)	33.20%		32.60%
Adjustment to deferred income tax liability balance due to adoption of ASU No. 2010-26			279,800,000
Adjustment to income tax expense balance due to adoption of ASU No. 2010-26			$ 7,700,000