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	Sep. 30, 2020	Dec. 31, 2019
Separate Accounts Disclosure [Abstract]
Variable annuity	$ 73,919	$ 74,965
VUL insurance	7,400	7,429
Other insurance	29	31
Threadneedle investment liabilities	4,780	5,063
Separate account liabilities	$ 86,128	$ 87,488