Retirement And Employee Benefit Plans (Amounts Recognized In Other Comprehensive Income) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss arising during the year	$ 25
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss arising during the year	(23)
Amortization of prior service cost
Amortization of net loss
Settlements
Tax effect	9
Total	(14)
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss arising during the year	(2)
Amortization of prior service cost
Amortization of net loss
Settlements
Tax effect	1
Total	$ (1)