Income Taxes:	9 Months Ended
Sep. 30, 2014
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes: As a regulated utility, GSWC treats certain temporary differences as flow-through adjustments in computing its income tax provision consistent with the income tax approach approved by the CPUC for ratemaking purposes. Flow-through adjustments increase or decrease tax expense in one period, with an offsetting decrease or increase occurring in another period. Giving effect to these temporary differences as flow-through adjustments typically results in a greater variance between the effective tax rate (“ETR”) and the statutory federal income tax rate in any given period than would otherwise exist if GSWC were not required to account for its income taxes as a regulated enterprise. The GSWC ETR was 40.7% and 38.2% for the three months ended September 30, 2014 and 2013, respectively, and 40.5% and 40.1% for the nine months ended September 30, 2014 and 2013, respectively. The GSWC ETRs deviated from the statutory rate primarily due to state taxes and differences between book and taxable income that are treated as flow-through adjustments in accordance with regulatory requirements (primarily related to plant, rate-case and compensation items), as well as permanent items. Changes in Tax Law: In September 2013, the U.S. Treasury Department issued final regulations related to the tax treatment of tangible property, including guidance on expensing certain repair and maintenance expenditures. The regulations are effective for tax years beginning on or after January 1, 2014. Registrant’s current tax treatment of tangible property continues to be permitted; however, Registrant is evaluating its water-pipeline tax repair-cost method, as well as other tax-method changes pursuant to these regulations. If Registrant adopts new methods, the impact to total income tax expense and the effective tax rate is not expected to be significant. In January 2013, the American Taxpayer Relief Act of 2012 extended 50% bonus depreciation for qualifying property through 2013. Although this change in law reduced AWR’s current taxes payable, it did not reduce its total income tax expense or ETR.

Income Taxes:

9 Months Ended

Sep. 30, 2014

Income Taxes:

As a regulated utility, GSWC treats certain temporary differences as flow-through adjustments in computing its income tax provision consistent with the income tax approach approved by the CPUC for ratemaking purposes. Flow-through adjustments increase or decrease tax expense in one period, with an offsetting decrease or increase occurring in another period. Giving effect to these temporary differences as flow-through adjustments typically results in a greater variance between the effective tax rate (“ETR”) and the statutory federal income tax rate in any given period than would otherwise exist if GSWC were not required to account for its income taxes as a regulated enterprise. The GSWC ETR was 40.7% and 38.2% for the three months ended September 30, 2014 and 2013, respectively, and 40.5% and 40.1% for the nine months ended September 30, 2014 and 2013, respectively. The GSWC ETRs deviated from the statutory rate primarily due to state taxes and differences between book and taxable income that are treated as flow-through adjustments in accordance with regulatory requirements (primarily related to plant, rate-case and compensation items), as well as permanent items.

Changes in Tax Law:

In September 2013, the U.S. Treasury Department issued final regulations related to the tax treatment of tangible property, including guidance on expensing certain repair and maintenance expenditures. The regulations are effective for tax years beginning on or after January 1, 2014. Registrant’s current tax treatment of tangible property continues to be permitted; however, Registrant is evaluating its water-pipeline tax repair-cost method, as well as other tax-method changes pursuant to these regulations. If Registrant adopts new methods, the impact to total income tax expense and the effective tax rate is not expected to be significant.

In January 2013, the American Taxpayer Relief Act of 2012 extended 50% bonus depreciation for qualifying property through 2013. Although this change in law reduced AWR’s current taxes payable, it did not reduce its total income tax expense or ETR.