Employee Benefit Arrangements - Defined Contribution Plans (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Retirement Benefits [Abstract]
Company match, percentage	6.00%
Award vesting percentage each year	25.00%
Cost recognized for defined contribution pension plans	$ 35	$ 39	$ 38