XML 42 R29.htm IDEA: XBRL DOCUMENT v3.5.0.2
Derivative Instruments (Details) - GOLDEN STATE WATER COMPANY
MWh in Thousands, $ in Thousands
1 Months Ended 3 Months Ended 6 Months Ended
Dec. 31, 2014
USD ($)
Jun. 30, 2016
USD ($)
MWh
Jun. 30, 2015
USD ($)
Jun. 30, 2016
USD ($)
Jun. 30, 2015
USD ($)
Derivative Instruments, Gain (Loss) [Line Items]          
Description of derivative activity volume | MWh   427      
Commodity Contract          
Derivative Instruments, Gain (Loss) [Line Items]          
Number of broker quotes received to determine fair value of derivative instrument   1   1  
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]          
Fair value at beginning of the period   $ (7,245) $ (6,176) $ (7,053) $ (3,339)
Unrealized gain (loss) on purchased power contracts   2,312 514 2,120 (2,323)
Fair value at end of the period $ (3,339) $ (4,933) $ (5,662) $ (4,933) $ (5,662)
Minimum | Commodity Contract          
Derivative Instruments, Gain (Loss) [Line Items]          
Term of derivative contract 3 years        
Maximum | Commodity Contract          
Derivative Instruments, Gain (Loss) [Line Items]          
Term of derivative contract 5 years