XML 50 R38.htm IDEA: XBRL DOCUMENT v3.8.0.1
INVESTMENTS - Additional Information (Detail)
$ in Millions
3 Months Ended 9 Months Ended
Sep. 30, 2017
USD ($)
investment
Jun. 30, 2017
USD ($)
investment
Mar. 31, 2017
investment
Sep. 30, 2016
investment
Dec. 31, 2016
USD ($)
Schedule of Investments [Line Items]          
Held to maturity securities transferred to available for sale securities, number of investments | investment 0 3 0 0  
Middle Market Loan Program Unfunded Amount $ 133       $ 91
Middle market loan commitments $ 530        
Percentage that the lending policy requires that the fair value of the securities and/or unrestricted cash received as collateral be of the fair value of the loaned securities 102.00%        
Allowance for loan losses for commercial mortgage loans and middle market loans $ 8       $ 3
Commercial mortgage loan commitments 103        
Held-to-maturity Securities, Transferred Security, at Carrying Value   $ 773      
Held-to-maturity Securities, Transferred Security, Unrealized Gain (Loss)   $ 47      
Limited partnerships investment commitments 365        
Parent Company and Other Business Segments          
Schedule of Investments [Line Items]          
Securities available for sale, fixed maturities, amortized cost 681        
Securities available for sale, fixed maturities, fair value $ 700