XML 102 R42.htm IDEA: XBRL DOCUMENT v3.21.1
ORGANIZATION, CONSOLIDATION AND BASIS OF PRESENTATION - (Narrative) (Details)
12 Months Ended
Feb. 21, 2018
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Premiums Written, Net | Homeowners' Insurance Product Line | Customer Concentration Risk | ISA        
Organization, Consolidation, And Basis of Preparation [Line Items]        
Concentration risk, percentage   20.70% 23.20% 23.80%
Premiums Written, Net | Homeowners' Insurance Product Line | Customer Concentration Risk | SageSure Insurance Managers LLC        
Organization, Consolidation, And Basis of Preparation [Line Items]        
Concentration risk, percentage   25.50% 23.10% 15.00%
Monarch National Insurance Company        
Organization, Consolidation, And Basis of Preparation [Line Items]        
VIE ownership percentage 100.00%