Represents the number of megawatts of base load energy that the entity will be able to purchase at a fixed price under the new agreement.

No definition available.

+ Details

Name:	awr_NewAgreementNumberOfMegawattsOfBaseLoadEnergyThatEntityWillBeAbleToPurchase
Namespace Prefix:	awr_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the number of broker quotes received in order to determine the fair value of the derivative instrument.

+ References

No definition available.

+ Details

Name:	awr_NumberOfBrokerQuotesReceivedToDetermineFairValueOfDerivativeInstrument
Namespace Prefix:	awr_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_DerivativeLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of gain (loss) recognized in earnings, arising from liabilities measured at fair value on a recurring basis using unobservable inputs (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 32

-Subparagraph c(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

This element represents a liability measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.

+ References

+ Details

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Derivative Instruments (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended	1 Months Ended	12 Months Ended
	Dec. 31, 2013 Purchase power contract quote	Jun. 30, 2013 GSWC MWs	Dec. 31, 2013 GSWC Purchase power contract	Dec. 31, 2012 GSWC Purchase power contract
Derivative instruments
Number of megawatts of base load energy that the entity will be able to purchase under the new agreement		12
Number of broker quotes received to determine fair value of derivative instrument	1
Changes in the fair value of the derivative
Balance, at beginning of the period			$ (3,060)	$ (7,611)
Unrealized gain on purchased power contracts			3,060	4,551
Balance, at end of the period			$ 0	$ (3,060)