Business, Basis of Presentation and Significant Accounting Policies - Amortization Methodologies Assumptions (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019 USD ($)
Deferred Policy Acquisition Cost [Line Items]
Deferred policy acquisition costs and value of business acquired amortization related to emergence of estimated gross profit	$ 1,478
Long-term equity return assumption	9.00%
Long-term equity return assumption, cap	14.00%
Long-term equity return assumption, look-forward period	5 years
Deferred policy acquisition cost
Deferred Policy Acquisition Cost [Line Items]
Deferred policy acquisition costs and value of business acquired amortization related to emergence of estimated gross profit	$ 904
Held for sale
Deferred Policy Acquisition Cost [Line Items]
Deferred policy acquisition costs and value of business acquired amortization related to emergence of estimated gross profit	$ 574