Available-for-Sale and Held-to-Maturity Securities (Details - Other) - USD ($)	1 Months Ended	3 Months Ended	12 Months Ended
	Jun. 30, 2019	Jun. 30, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Investments, Debt and Equity Securities [Abstract]
Net impairment			$ 0	$ 0	$ 0
Components of gains (losses) on securities and other, net
Debt Securities, Available-for-sale, Realized Gain			51,000,000	98,000,000	40,000,000
Debt Securities, Available-for-sale, Realized Loss		$ (80,000,000)	(80,000,000)	(54,000,000)	0
Debt Securities, Available-for-sale, Realized Gain (Loss)			(29,000,000)	44,000,000	40,000,000
Equity method investment income (loss) and other(3)(4)			6,000,000	9,000,000	(12,000,000)
Gains (losses) on securities and other, net			(23,000,000)	53,000,000	28,000,000
Investment securities, amount sold	$ 4,500,000,000
Deposits transferred to third-party banks	$ 6,600,000,000
Equity method investment, realized gain on disposal				5,000,000
Gain (loss) on interest rate fair value hedge ineffectiveness			$ (3,000,000)	$ (19,000,000)	$ (14,000,000)