Income Taxes - Significant Portions of Deferred Tax Assets and Deferred Tax Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Deferred tax assets:
Fixed maturity investments	$ 0	$ 4,279
Carryover of tax losses	5,962	5,534
Total gross deferred tax assets	5,962	9,813
Deferred tax liabilities:
Unrealized gains	713,879	808,071
Employee and agent compensation	93,738	88,012
Deferred acquisition costs	723,337	688,034
Future policy benefits, unearned and advance premiums, and policy claims	226,943	257,640
Other liabilities	15,738	7,209
Total gross deferred tax liabilities	1,773,635	1,848,966
Net deferred tax liability	$ 1,767,673	$ 1,839,153