Policyholder Account Balances, Future Policy Benefits and Claims and Separate Account Liabilities Policyholder Account Balances, Future Policy Benefits and Claims and Separate Account Liabilities (Separate Account Liabilities) (Details 2) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Separate Accounts Disclosure [Abstract]
Variable annuity	$ 79,862	$ 79,299
VUL insurance	8,539	8,226
Other insurance	32	31
Threadneedle investment liabilities	5,050	5,055
Separate account liabilities	$ 93,483	$ 92,611