XML 113 R86.htm IDEA: XBRL DOCUMENT v3.3.1.900
Indebtedness (Covenants in the Line of Credit) (Details) - USD ($)
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Debt Disclosure [Abstract]      
Consolidated net worth, required $ 960,000,000    
Statutory surplus, required $ 750,000,000    
Debt-to-capitalization ratio, required [1] 35.00%    
Consolidated net worth, actual $ 1,398,041,000 $ 1,275,586,000 $ 1,153,928,000
Statutory surplus, actual $ 1,426,300,000 $ 1,307,800,000  
Debt-to-capitalization ratio, actual [1] 22.10%    
[1] Calculated in accordance with Line of Credit agreement.