Other Expenses (Other Expenses) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Other Income and Expenses [Abstract]
Employee related costs	$ 3,664	$ 3,595	$ 3,840
Third party staffing costs	1,703	1,693	1,619
General and administrative expenses	910	1,129	1,007
Pension, postretirement and postemployment benefit costs	185	307	400
Premium taxes, other taxes, and licenses & fees	758	842	688
Commissions and other variable expenses	5,707	5,387	5,741
Capitalization of DAC	(3,254)	(3,002)	(3,152)
Amortization of DAC and VOBA	2,975	2,681	2,718
Amortization of negative VOBA	(56)	(140)	(269)
Interest expense on debt	1,122	1,129	1,157
Total other expenses	$ 13,714	$ 13,621	$ 13,749