| Standard label: | Cost of Purchased Water | 
| Name: | us-gaap:CostOfPurchasedWater | 
| Documentation: | Cost of water purchased, may include any water related assessment. If water is bought on a unit volume basis, would also be considered as commodity costs. | 
| Object type: | cm:Concept | 
| Data type: | Monetary (xbrli:monetaryItemType) | 
| Period type: | For Period (duration) | 
| Balance type: | Debit | 
| Abstract: | false | 
| Workiva Wdesk Taxonomy Analyzer: | us-gaap:CostOfPurchasedWater | 
| Label | Role | Language | 
| Cost of Purchased Water | http://www.xbrl.org/2003/role/label | en-US | 
| Reference | Role | Topic | 
| FASB Accounting Standards Codification 220 10 S99 2 (SX 210.5-03.2) | http://fasb.org/us-gaap/role/ref/legacyRef | 220 | 
| Part Of Roll Up: | 
| us-gaap:DirectOperatingCosts |