Note 6 - Investments Cost and Equity Method Investments (Details) (Co-venturer [Member], USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012
Co-venturer [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investments	$ 130
Payments to Acquire Interest in Joint Venture	$ 12

The cash outflow associated with the investment in or advances to an entity in which the reporting entity shares control of the entity with another party or group.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3213-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 17

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration