Note 5 - Employee Benefit Plans (Details) - Employee Benefit Plans (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Pension Plan, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 7	$ 7	$ 22	$ 21
Interest cost	11	10	32	32
Expected return on plan assets	(16)	(16)	(47)	(48)
Net amortization of prior service cost			(1)	(1)
Recognized actuarial loss	9	9	26	26
Net periodic pension benefit cost	11	10	32	30
Other Postretirement Benefit Plan, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	1	1	2	3
Interest cost	3	4	10	12
Expected return on plan assets	(1)	(1)	(4)	(4)
Net amortization of prior service cost	(1)	(1)	(3)	(2)
Recognized actuarial loss	2	2	6	7
Net periodic pension benefit cost	$ 4	$ 5	$ 11	$ 16