Shareholders' Equity (Details - Other Comprehensive Income Activity) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2020	Jun. 30, 2019
Available-for-sale securities, before tax
Unrealized gains (losses), before tax	$ 193		$ 86		$ 21	$ 236
Reclassification into earnings, before tax	(22)		65		(41)	55
Net change from available-for-sale securities, before tax	171		151		(20)	291
Available-for-sale securities, tax effect
Unrealized gains (losses), tax effect	(51)		(22)		(5)	(60)
Reclassification into earnings, tax effect	6		(17)		11	(14)
Net change from available-for-sale securities, tax effect	(45)		(39)		6	(74)
Available-for-sale securities, after tax
Unrealized gains (losses), after tax	142		64		16	176
Reclassification into earnings, after tax	(16)		48		(30)	41
Net change from available-for-sale securities	126		112		(14)	217
Other comprehensive income (loss), before tax	171		151		(20)	291
Other comprehensive income (loss), tax effect	(45)		(39)		6	(74)
Other comprehensive income (loss)	$ 126	$ (140)	$ 112	$ 105	$ (14)	$ 217

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