Note 2 - Significant Accounting Policies and Methods of Application (Details) - Cost of Goods Sold Adjustments (USD $) In Millions, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Note 2 - Significant Accounting Policies and Methods of Application (Details) - Cost of Goods Sold Adjustments [Line Items]
LOCOM adjustments	$ 77		$ 9		$ 23
Retail Operations [Member]
Note 2 - Significant Accounting Policies and Methods of Application (Details) - Cost of Goods Sold Adjustments [Line Items]
LOCOM adjustments	4		1		3
Wholesale Services [Member]
Note 2 - Significant Accounting Policies and Methods of Application (Details) - Cost of Goods Sold Adjustments [Line Items]
LOCOM adjustments	73	[1]	8	[1]	19	[1]
Midstream Operations [Member]
Note 2 - Significant Accounting Policies and Methods of Application (Details) - Cost of Goods Sold Adjustments [Line Items]
LOCOM adjustments					$ 1

[1] The significant in 2014 was due to a significant decline in natural gas prices in December 2014.