Regulatory Matters: General Rate Case Memorandum Accounts and Other Regulatory Assets (Details) (USD $)	3 Months Ended	6 Months Ended							3 Months Ended
	Jun. 30, 2014 customer	Jun. 30, 2014	Jun. 30, 2014 GSWC	Dec. 31, 2013 GSWC	Jun. 30, 2014 GSWC General rate case memorandum accounts	Dec. 31, 2013 GSWC General rate case memorandum accounts	Jun. 30, 2014 GSWC Other regulatory assets, net	Dec. 31, 2013 GSWC Other regulatory assets, net	Sep. 30, 2013 Minimum GSWC General rate case memorandum accounts	Sep. 30, 2013 Maximum GSWC General rate case memorandum accounts	Sep. 30, 2013 Majority GSWC General rate case memorandum accounts
Regulatory matters:
Regulatory assets			$ 113,305,000	$ 122,681,000	$ 9,868,000	$ 15,645,000	$ 20,066,000	$ 25,086,000
Net regulatory assets increase (decrease) due to settlement of rate case		$ 5,800,000
Regulatory asset recovery periods									12 months	24 months	12 months
Number of Customers in new service territory	17,000