Consolidated Statements of Operations and Comprehensive Income (Parenthetical) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Total net realized gains (losses) reclassified from AOCI	$ (38)	$ 10	$ (142)	$ 27
Income tax expense on reclassified unrealized gains and loses	(4)	0	(19)	3
Stockholders' Equity Attributable to Parent	$ 50,934	$ 50,471	$ 50,934	$ 50,471

Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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Amount before tax of reclassification adjustments of other comprehensive income (loss).

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