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	Jun. 30, 2020	Dec. 31, 2019
Separate Accounts Disclosure [Abstract]
Variable annuity	$ 71,990	$ 74,965
VUL insurance	7,041	7,429
Other insurance	28	31
Threadneedle investment liabilities	4,639	5,063
Separate account liabilities	$ 83,698	$ 87,488