Equity (Reclassifications Out of Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net investment gains (losses)	$ (19)	$ (10)
Net investment income	896	788
Net derivative gains (losses)	6,747	(1,310)
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	6,104	(975)
Income tax (expense) benefit	(1,265)	221
Net income (loss)	4,839	(754)
Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net income (loss)	10	(2)
Reclassification out of Accumulated Other Comprehensive Income | Net unrealized investment gains (losses):
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net investment gains (losses)	12	(24)
Net derivative gains (losses)	(2)	(4)
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	10	(28)
Income tax (expense) benefit	(2)	6
Net income (loss)	8	(22)
Reclassification out of Accumulated Other Comprehensive Income | Unrealized gains (losses) on derivatives - cash flow hedges:
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	2	26
Income tax (expense) benefit	0	(6)
Net income (loss)	2	20
Reclassification out of Accumulated Other Comprehensive Income | Unrealized gains (losses) on derivatives - cash flow hedges: | Interest rate swaps
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net investment income	1	1
Net derivative gains (losses)	1	22
Reclassification out of Accumulated Other Comprehensive Income | Unrealized gains (losses) on derivatives - cash flow hedges: | Foreign currency swaps
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net derivative gains (losses)	$ 0	$ 3