Investments - Schedule of Fixed Maturities by Contractual Maturity (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Fixed Maturities Available for Sale, Amortized Cost
Due in one year or less	$ 66,545
Due from one to five years	535,903
Due from five to ten years	1,051,912
Due from ten to twenty years	3,877,844
Due after twenty years	7,635,180
Mortgage-backed and asset-backed securities	84,487
Cost or Amortized Cost	13,251,871	$ 12,823,612
Fixed Maturities Available for Sale, Fair Value
Due in one year or less	67,585
Due from one to five years	583,237
Due from five to ten years	1,129,107
Due from ten to twenty years	4,201,334
Due after twenty years	7,684,715
Mortgage-backed and asset-backed securities	92,046
Total fixed maturities available for sale, Fair Value	$ 13,758,024	$ 14,493,060	[1]

[1] Certain balances were adjusted to give effect to discontinued operations as described in Note 1—Significant Accounting Policies.