Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 12

-Paragraph 10

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=6959260&loc=d3e187085-122770

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.29)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 30

-Article 5

Name:	us-gaap_CommonStockSharesOutstanding
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

CONSOLIDATED STATEMENTS OF CAPITALIZATION (Parenthetical)	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013 6.64% notes due 2013	Dec. 31, 2012 6.64% notes due 2013	Dec. 31, 2013 6.64% notes due 2013 GSWC	Dec. 31, 2012 6.64% notes due 2013 GSWC	Dec. 31, 2013 6.80% notes due 2013	Dec. 31, 2012 6.80% notes due 2013	Dec. 31, 2013 6.80% notes due 2013 GSWC	Dec. 31, 2012 6.80% notes due 2013 GSWC	Dec. 31, 2013 6.87% notes due 2023	Dec. 31, 2012 6.87% notes due 2023	Dec. 31, 2013 6.87% notes due 2023 GSWC	Dec. 31, 2012 6.87% notes due 2023 GSWC	Dec. 31, 2013 7.00% notes due 2023	Dec. 31, 2012 7.00% notes due 2023	Dec. 31, 2013 7.00% notes due 2023 GSWC	Dec. 31, 2012 7.00% notes due 2023 GSWC	Dec. 31, 2013 6.81% notes due 2028	Dec. 31, 2012 6.81% notes due 2028	Dec. 31, 2013 6.81% notes due 2028 GSWC	Dec. 31, 2012 6.81% notes due 2028 GSWC	Dec. 31, 2013 6.59% notes due 2029	Dec. 31, 2012 6.59% notes due 2029	Dec. 31, 2013 6.59% notes due 2029 GSWC	Dec. 31, 2012 6.59% notes due 2029 GSWC	Dec. 31, 2013 7.875% notes due 2030	Dec. 31, 2012 7.875% notes due 2030	Dec. 31, 2013 7.875% notes due 2030 GSWC	Dec. 31, 2012 7.875% notes due 2030 GSWC	Dec. 31, 2013 7.23% notes due 2031	Dec. 31, 2012 7.23% notes due 2031	Dec. 31, 2013 7.23% notes due 2031 GSWC	Dec. 31, 2012 7.23% notes due 2031 GSWC	Dec. 31, 2013 6.00% notes due 2041	Dec. 31, 2012 6.00% notes due 2041	Dec. 31, 2013 6.00% notes due 2041 GSWC	Dec. 31, 2012 6.00% notes due 2041 GSWC	Dec. 31, 2013 5.87% private placement notes due 2028	Dec. 31, 2012 5.87% private placement notes due 2028	Dec. 31, 2013 5.87% private placement notes due 2028 GSWC	Dec. 31, 2012 5.87% private placement notes due 2028 GSWC	Dec. 31, 2013 6.70% private placement notes due 2019	Dec. 31, 2012 6.70% private placement notes due 2019	Dec. 31, 2013 6.70% private placement notes due 2019 GSWC	Dec. 31, 2012 6.70% private placement notes due 2019 GSWC	Dec. 31, 2013 5.50% tax-exempt obligation due 2026	Dec. 31, 2012 5.50% tax-exempt obligation due 2026	Dec. 31, 2013 5.50% tax-exempt obligation due 2026 GSWC	Dec. 31, 2012 5.50% tax-exempt obligation due 2026 GSWC
Interest rate per annum (as a percent)			6.64%	6.64%	6.64%	6.64%	6.80%	6.80%	6.80%	6.80%	6.87%	6.87%	6.87%	6.87%	7.00%	7.00%	7.00%	7.00%	6.81%	6.81%	6.81%	6.81%	6.59%	6.59%	6.59%	6.59%	7.875%	7.875%	7.875%	7.875%	7.23%	7.23%	7.23%	7.23%	6.00%	6.00%	6.00%	6.00%	5.87%	5.87%	5.87%	5.87%	6.70%	6.70%	6.70%	6.70%	5.50%	5.50%	5.50%	5.50%
Common stock, shares authorized	60,000,000	30,000,000
Common stock, shares outstanding	38,720,693	38,720.693