EMPLOYEE BENEFIT PLANS (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011
Schedule of Employee Benefit Plans [Line Items]
Defined Contribution Plan, Cost Recognized	$ 24.2	$ 19.5
UNITED STATES
Schedule of Employee Benefit Plans [Line Items]
Defined Contribution Plan Employer Matching Contribution Percent	50.00%
Defined Contribution Plan Maximum Annual Contribution Per Employee Percent	6.00%
Minimum [Member] | CANADA
Schedule of Employee Benefit Plans [Line Items]
Defined Contribution Plan Maximum Annual Contribution Per Employee Percent	1.00%
Maximum [Member] | CANADA
Schedule of Employee Benefit Plans [Line Items]
Defined Contribution Plan Maximum Annual Contribution Per Employee Percent	7.00%