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Debt Instrument, Maximum Borrowing Capacity

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Represents the number of customers who are served by the entity.

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Represents the number of registrants filing combined report during the period.

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Represents the period of fixed price contracts to operate and maintain the water and/or wastewater systems at various military bases.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Cost associated with reimbursable income. This occurs when a services entity incurs expenses on behalf of the client and passes through the cost of reimbursable expenses to a client.

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Face (par) amount of debt instrument at time of issuance.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The amount for notes payable (written promise to pay), due to related parties.

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Amount of transactions with related party during the financial reporting period.

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All taxes not related to income of the entity or excise or sales taxes levied on the revenue of the entity that are not reported elsewhere. These taxes could include production, real estate, personal property, and pump tax.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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Summary of Significant Accounting Policies: (Details) (USD $)	3 Months Ended
	Mar. 31, 2015 registrant	Mar. 31, 2014	May 31, 2013
Basis of Presentation:
Number of registrants filing combined report	2
Related Party Transactions
Amounts outstanding under note	$ 0
Sales and Use Taxes:
Non-income tax assessments accounted on a gross basis	4,276,000	4,325,000
Debt Issuance Cost	5,100,000us-gaap_UnamortizedDebtIssuanceExpense
AWR \| Promissory Note
Related Party Transactions
Debt instrument, face amount			20,000,000.0
Debt instrument, maximum borrowing capacity			20,000,000.0
AWR \| Syndicated Credit Facility
Related Party Transactions
Maximum borrowing capacity on line of credit	100,000,000
GOLDEN STATE WATER COMPANY
Related Party Transactions
Payments to affiliate for corporate office administrative and general costs	707,000	696,000
Sales and Use Taxes:
Franchise fees billed to customers and recorded as operating revenue	871,000	845,000
Non-income tax assessments accounted on a gross basis	3,918,000	3,896,000
GOLDEN STATE WATER COMPANY \| Purchase, production, distribution and sale of water
Nature of Operations:
Number of customers served	258,000
GOLDEN STATE WATER COMPANY \| Electricity distribution
Nature of Operations:
Number of customers served	24,000
ASUS
Sales and Use Taxes:
Non-income tax assessments accounted on a gross basis	$ 32,000	$ 149,000
ASUS \| Contracts
Nature of Operations:
Period of fixed price contracts to operate and maintain the water and/or wastewater systems at various military bases	50 years
Sales and Use Taxes:
Period of fixed price contracts to operate and maintain the water and/or wastewater systems at various military bases	50 years
Sales \| GOLDEN STATE WATER COMPANY \| Purchase, production, distribution and sale of water
Nature of Operations:
Percentage of total revenue	90.00%