Collateral Financing Arrangements Collateral Financing Arrangements (Associated with Closed Block) (Details) - Met Life Reinsurance Company Of Charleston [Member] - Secured Debt [Member] - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Debt Instrument, Principal Outstanding	$ 1,060	$ 1,121
Other Receivables	139	146
Pledged Assets Separately Reported, Securities Pledged for Other Debt Obligations, at Fair Value	83	97
Invested Assets On Deposit Held In Trust And Pledged As Collateral	$ 1,370	$ 1,248