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v3.3.1.900

Summary of Significant Accounting Policies (Details) customer in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2015 USD ($) registrant customer | Dec. 31, 2014 USD ($) | Dec. 31, 2013 USD ($) | Oct. 27, 2015 USD ($)
Summary of significant accounting policies |  |  |  |
Unamortized Debt Issuance Expense | $ 4,700,000 |  |  |
Related Party Transaction, Amounts of Transaction | $ 2,600,000 | $ 2,700,000 | $ 2,600,000 |
Basis of Presentation: |  |  |  |
Number of registrants filing combined report | registrant | 2 |  |  |
Impairment of Long-Lived Assets |  |  |  |
Impairment of long-lived assets | $ 0 |  |  |
Goodwill |  |  |  |
Goodwill arose from acquisition of subcontractor's business | 1,100,000 | 1,100,000 |  |
Sales and Use Taxes: |  |  |  |
Non-income tax assessments accounted on a gross basis | $ 16,636,000 | $ 16,722,000 | $ 15,865,000 |
Military Utility Privatization Subsidiaries |  |  |  |
Summary of significant accounting policies |  |  |  |
Period of Fixed Price Contracts to Maintain Water Systems at Various Military Bases | 50 years |  |  |
GSWC |  |  |  |
Property and Depreciation |  |  |  |
Aggregate composite rate for depreciation (as a percent) | 3.20% | 3.20% | 3.35% |
Depreciation on transportation equipment | $ 641,000 | $ 678,000 | $ 877,000 |
Estimated useful lives of utility plant, as authorized by the CPUC |  |  |  |
Generation | 40 years |  |  |
Interest |  |  |  |
Amount recorded in AFUDC | $ 694,000 | 24,000 | 270,000 |
Alternative-Revenue Programs |  |  |  |
Number of months within which expected additional revenue collection is recorded | 24 months |  |  |
Advances for Construction and Contributions in aid of Constructions |  |  |  |
Period for refund of advances for construction | 40 years |  |  |
Fair Value of Financial Instruments |  |  |  |
Long-term debt-GSWC | $ 403,844,000 |  |  |
Sales and Use Taxes: |  |  |  |
Franchise fees billed to customers and recorded as operating revenue | 3,800,000 | 3,700,000 | 3,600,000 |
Non-income tax assessments accounted on a gross basis | 15,244,000 | 15,221,000 | 14,072,000 |
GSWC | Fair Value, Inputs, Level 1 [Member] |  |  |  |
Fair Value of Financial Instruments |  |  |  |
Long-term debt-GSWC | 0 |  |  |
GSWC | Fair Value, Inputs, Level 3 [Member] |  |  |  |
Fair Value of Financial Instruments |  |  |  |
Long-term debt-GSWC | 0 |  |  |
GSWC | Carrying Amount |  |  |  |
Fair Value of Financial Instruments |  |  |  |
Long-term debt-GSWC | 325,853,000 | 326,090,000 |  |
GSWC | Fair Value |  |  |  |
Fair Value of Financial Instruments |  |  |  |
Long-term debt-GSWC |  | 417,057,000 |  |
GSWC | Fair Value | Level 2 |  |  |  |
Fair Value of Financial Instruments |  |  |  |
Long-term debt-GSWC | $ 403,844,000 |  |  |
GSWC | Minimum |  |  |  |
Estimated useful lives of utility plant, as authorized by the CPUC |  |  |  |
Source of water supply | 30 years |  |  |
Pumping | 25 years |  |  |
Water treatment | 20 years |  |  |
Transmission and distribution | 25 years |  |  |
Other plant | 7 years |  |  |
GSWC | Maximum |  |  |  |
Estimated useful lives of utility plant, as authorized by the CPUC |  |  |  |
Source of water supply | 50 years |  |  |
Pumping | 40 years |  |  |
Water treatment | 35 years |  |  |
Transmission and distribution | 55 years |  |  |
Other plant | 40 years |  |  |
GSWC | Notes Payable, Other Payables [Member] |  |  |  |
Related Party Transactions |  |  |  |
Debt Instrument, Face Amount |  |  |  | $ 40,000,000
Debt Instrument, Maximum Borrowing Capacity |  |  |  | 40,000,000
GSWC | Purchase, production, distribution and sale of water |  |  |  |
Nature of Operations: |  |  |  |
Number of customers served | customer | 260 |  |  |
Interest |  |  |  |
Weighted cost of capital (as a percent) | 8.34% |  |  |
GSWC | Electric |  |  |  |
Nature of Operations: |  |  |  |
Number of customers served | customer | 24 |  |  |
Sales and Use Taxes: |  |  |  |
Cost Of Debt Percent | 6.96% |  |  |
American States Utility Services [Member] |  |  |  |
Sales and Use Taxes: |  |  |  |
Non-income tax assessments accounted on a gross basis | $ 367,000 | $ 490,000 | $ 864,000 |
American States Utility Services [Member] | Notes Payable, Other Payables [Member] |  |  |  |
Related Party Transactions |  |  |  |
Debt Instrument, Face Amount |  |  |  | 10,000,000
Debt Instrument, Maximum Borrowing Capacity |  |  |  | $ 10,000,000
American States Utility Services [Member] | Military Utility Privatization Subsidiaries |  |  |  |
Nature of Operations: |  |  |  |
Period of fixed price contracts to operate and maintain the water and/or wastewater systems at various military bases | 50 years |  |  |
AWR |  |  |  |
Related Party Transactions |  |  |  |
Maximum borrowing capacity on line of credit | $ 100,000,000.0 |  |  |
Notes Receivable | AWR | Notes Payable, Other Payables [Member] |  |  |  |
Related Party Transactions |  |  |  |
Notes Receivable, Related Parties, Current | $ 0 |  |  |
Sales [Member] | GSWC | Purchase, production, distribution and sale of water |  |  |  |
Nature of Operations: |  |  |  |
Percentage of total revenues | 90.00% | 90.00% | 90.00% |
Syndicated revolving credit facility | AWR | Syndicated revolving credit facility |  |  |  |
Related Party Transactions |  |  |  |
Maximum borrowing capacity on line of credit | $ 100,000,000 |  |  |

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