XML 50 R38.htm IDEA: XBRL DOCUMENT v3.10.0.1
Investments (Fixed Income Securities by Contractual Maturity) (Details) - USD ($)
$ in Thousands
Sep. 30, 2018
Dec. 31, 2017
Schedule of Fixed Income Securities [Line Items]    
Due in one year or less fair value, AFS $ 176,545  
Due after one year through five years fair value, AFS 2,107,663  
Due after five years through 10 years fair value, AFS 2,759,167  
Due after 10 years fair value, AFS 146,781  
AFS, Fair Value 5,190,156 $ 5,162,522
Due in one year or less carrying value, HTM 14,017  
Due after one year through five years carrying value, HTM 20,518  
Due after five years through 10 years carrying value, HTM 10,047  
Due after 10 years carrying value, HTM 0  
HTM, Carrying Value 44,582 42,129
Due in one year or less fair value, HTM 14,150  
Due after one year through five years fair value, HTM 21,926  
Due after five years through 10 years fair value, HTM 10,164  
Due after 10 years fair value, HTM 0  
HTM, Fair Value $ 46,240 $ 44,100