v3.10.0.1
Document and Entity Information - shares
6 Months Ended
Jun. 30, 2018
Jul. 20, 2018
Document and Entity Information [Abstract]    
Document Type 10-Q  
Amendment Flag false  
Document Fiscal Period Focus Q2  
Document Period End Date Jun. 30, 2018  
Document Fiscal Year Focus 2018  
Current Fiscal Year End Date --12-31  
Entity Registrant Name PICO HOLDINGS INC /NEW  
Entity Central Index Key 0000830122  
Entity Filer Category Accelerated Filer  
Entity Common Stock, Shares Outstanding   21,907,253