Other Income and Expense Items	12 Months Ended
Dec. 31, 2011
Notes to Financial Statements [Abstract]
Other Income and Expense Items	22. Other Income and Expense Items Other, net income for the year ended December 31, 2009 totaling $21.4 million consists primarily of $20.3 million of settlements with insurance companies related to certain environmental matters and collection of a $1.9 million settlement amount awarded to the Company related to the Southwest Gas litigation action filed by the Company in 2002 against former Arizona Corporation Commissioner James Irvin. These contingent gains were recognized in 2009 when the related settlement awards were received.

The entire disclosure for other income or other expense items (both operating and nonoperating). Sources of nonoperating income or nonoperating expense that may be disclosed, include amounts earned from dividends, interest on securities, profits (losses) on securities, net and miscellaneous other income or income deductions.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 5

-Section 03

-Paragraph 3, 6, 7, 9

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.3,6,7,9)

-URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688

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