EMPLOYEE BENEFIT PLANS (DETAILS) (USD $) In Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Qualified defined benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 8.7	$ 8.1	$ 26.7	$ 24.3
Interest cost	18.1	16.9	54.7	50.7
Expected return on asets	(22.0)	(17.7)	(66.2)	(53.1)
Amortization of prior service cost	(0.3)	(0.2)	(0.7)	(0.6)
Actuarial loss	5.5	5.5	17.7	16.5
Net pension expense	10.0	12.6	32.2	37.8
Defined Benefit Plan, Contributions by Employer	11.1	15.2	33.4	45.6
Nonqualified defined benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Net pension expense	1.1	0.8	3.0	2.3
Post retirement medical benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Net pension expense	$ 3.6	$ 3.1	$ 11.0	$ 9.3