INVESTMENTS - Total Investments in Bank and Financial Institution Sector, Including those Classified as Perpetual Securities (Detail) (Banks/financial Institutions, USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Summary of Investment Holdings [Line Items]
Amortized Cost	$ 12,884	$ 15,205
Fair Value	14,121	15,375
Percentage of Total Investment Portfolio, Amortized Cost	14.00%	15.00%
Percentage of Total Investment Portfolio, Fair Value	13.00%	15.00%
Fixed maturities
Summary of Investment Holdings [Line Items]
Amortized Cost	10,627	12,427
Fair Value	11,683	12,637
Percentage of Total Investment Portfolio, Amortized Cost	11.00%	12.00%
Percentage of Total Investment Portfolio, Fair Value	11.00%	12.00%
Perpetual securities | Upper Tier II
Summary of Investment Holdings [Line Items]
Amortized Cost	1,554	1,920
Fair Value	1,645	1,913
Percentage of Total Investment Portfolio, Amortized Cost	2.00%	2.00%
Percentage of Total Investment Portfolio, Fair Value	1.00%	2.00%
Perpetual securities | Tier I
Summary of Investment Holdings [Line Items]
Amortized Cost	703	858
Fair Value	$ 793	$ 825
Percentage of Total Investment Portfolio, Amortized Cost	1.00%	1.00%
Percentage of Total Investment Portfolio, Fair Value	1.00%	1.00%