Shareholders' Equity (Details - Reclassification Out Of Accumulated Other Comprehensive Loss) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Reclassification Adjustment out of Accumulated Other Comprehensive Income (Loss) [Line Items]
Gains (losses) on securities and other, net									$ (23)	$ 53	$ 28
Interest income									2,111	2,009	1,571
Reclassification into earnings, net									1,319	1,418	1,064
Income tax (expense) benefit									(364)	(366)	(450)
Other Non-interest expense									(94)	(77)	(76)
Net income	$ 172	$ 274	$ 219	$ 290	$ 270	$ 285	$ 250	$ 247	955	1,052	614
Available-for-sale securities | Reclassification out of Accumulated Other Comprehensive Income (Loss)
Reclassification Adjustment out of Accumulated Other Comprehensive Income (Loss) [Line Items]
Gains (losses) on securities and other, net									(29)	45	39
Interest income									(3)	(3)	0
Reclassification into earnings, net									(32)	42	39
Income tax (expense) benefit									9	(11)	(15)
Net income									(23)	31	24
Foreign currency translation | Reclassification out of Accumulated Other Comprehensive Income (Loss)
Reclassification Adjustment out of Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Non-interest expense									0	0	2
Net income									$ 0	$ 0	$ 2