XML 45 R33.htm IDEA: XBRL DOCUMENT v3.7.0.1
Fair Value Measurement (Details) - USD ($)
$ in Thousands
Jun. 30, 2017
Dec. 31, 2016
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Long-term debt $ 430,926 $ 433,460
Significant Observable Inputs    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Long-term debt, fair value 525,609 502,446
Quoted Prices in Active Markets for Identical Assets    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Investment in California Water Service Group $ 3,680 $ 3,390