Lines of Credit	12 Months Ended
Dec. 31, 2012
Line of Credit Facility [Abstract]
LINES OF CREDIT	Lines of Credit On March 1, 2012, SJW Corp., SJW Land Company and Wells Fargo Bank, National Association (“Wells Fargo”) entered into a credit agreement which provides for an unsecured revolving credit facility in an aggregate amount of $15,000. This credit agreement expanded and replaced SJW Corp.’s and SJW Land Company’s existing credit facility with Wells Fargo. In addition, San Jose Water Company and Wells Fargo entered into a credit agreement which provides for an unsecured revolving credit facility in an aggregate amount of $75,000. This credit agreement replaced San Jose Water Company’s existing credit facility with Wells Fargo. On January 11, 2013, SJW Corp., SJW Land Company, San Jose Water Company and Wells Fargo amended their respective credit agreements dated March 1, 2012, to clarify defined terms in the funded debt and interest coverage ratio covenants. As of December 31, 2012, SJW Corp. and its subsidiaries had unsecured bank lines of credit, allowing aggregate short-term borrowings of up to $90,000. San Jose Water Company has issued two standby letters of credit with a commercial bank in the amount of $3,000 in support of its SDWSRF loans which were funded in 2005 and 2008. The letters of credit automatically renew for one year each December unless the issuing bank elects not to renew it, and the amount of coverage can be reduced as the loan principal balance decreases. As of December 31, 2012, $3,000 under the San Jose Water Company line of credit is set aside as security for its SDWSRF loans. The lines of credit bear interest at variable rates, and will expire on September 1, 2014. As of December 31, 2012 and 2011, SJW Corp. has an outstanding balance on the lines of credit of $15,300 and $0, respectively. Cost of borrowing on the lines of credit averaged 1.44% and 1.64% as of December 31, 2012 and 2011, respectively. SJW Corp., on a consolidated basis, and San Jose Water Company have the following affirmative covenants on their unsecured bank lines of credit: (1) the funded debt cannot exceed 66-2/3% of total capitalization, and (2) net income available for interest charges for the trailing 12-calendar-month period cannot be less than 175% of interest charges. As of December 31, 2012, SJW Corp. and San Jose Water Company, respectively, were in compliance with the unsecured bank line of credit affirmative covenants.

Lines of Credit

On March 1, 2012, SJW Corp., SJW Land Company and Wells Fargo Bank, National Association (“Wells Fargo”) entered into a credit agreement which provides for an unsecured revolving credit facility in an aggregate amount of $15,000. This credit agreement expanded and replaced SJW Corp.’s and SJW Land Company’s existing credit facility with Wells Fargo. In addition, San Jose Water Company and Wells Fargo entered into a credit agreement which provides for an unsecured revolving credit facility in an aggregate amount of $75,000. This credit agreement replaced San Jose Water Company’s existing credit facility with Wells Fargo.

On January 11, 2013, SJW Corp., SJW Land Company, San Jose Water Company and Wells Fargo amended their respective credit agreements dated March 1, 2012, to clarify defined terms in the funded debt and interest coverage ratio covenants.

As of December 31, 2012, SJW Corp. and its subsidiaries had unsecured bank lines of credit, allowing aggregate short-term borrowings of up to $90,000. San Jose Water Company has issued two standby letters of credit with a commercial bank in the amount of $3,000 in support of its SDWSRF loans which were funded in 2005 and 2008. The letters of credit automatically renew for one year each December unless the issuing bank elects not to renew it, and the amount of coverage can be reduced as the loan principal balance decreases. As of December 31, 2012, $3,000 under the San Jose Water Company line of credit is set aside as security for its SDWSRF loans. The lines of credit bear interest at variable rates, and will expire on September 1, 2014. As of December 31, 2012 and 2011, SJW Corp. has an outstanding balance on the lines of credit of $15,300 and $0, respectively. Cost of borrowing on the lines of credit averaged 1.44% and 1.64% as of December 31, 2012 and 2011, respectively.

SJW Corp., on a consolidated basis, and San Jose Water Company have the following affirmative covenants on their unsecured bank lines of credit: (1) the funded debt cannot exceed 66-2/3% of total capitalization, and (2) net income available for interest charges for the trailing 12-calendar-month period cannot be less than 175% of interest charges. As of December 31, 2012, SJW Corp. and San Jose Water Company, respectively, were in compliance with the unsecured bank line of credit affirmative covenants.