XML 158 R131.htm IDEA: XBRL DOCUMENT v3.8.0.1
Segment Information (Net Premiums Earned By Geographic Region) (Details)
12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Segment Reporting Information [Line Items]      
Net Premiums Earned by Geographic Region

North America

 
Europe (1)

 
Asia Pacific / Far East

 
Latin America

2017
70
%
 
11
%
 
12
%
 
7
%
2016
70
%
 
12
%
 
11
%
 
7
%
2015
60
%
 
15
%
 
15
%
 
10
%
   
North America [Member]      
Segment Reporting Information [Line Items]      
Percentage of net premiums earned by geographic region 70.00% 70.00% 60.00%
Europe [Member]      
Segment Reporting Information [Line Items]      
Percentage of net premiums earned by geographic region [1] 11.00% 12.00% 15.00%
Asia Pacific and Far East [Member]      
Segment Reporting Information [Line Items]      
Percentage of net premiums earned by geographic region 12.00% 11.00% 15.00%
Latin America [Member]      
Segment Reporting Information [Line Items]      
Percentage of net premiums earned by geographic region 7.00% 7.00% 10.00%
[1] (1) Europe includes Eurasia and Africa region.