Consolidated Comprehensive Income Statement (unaudited) (Parenthetical) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2021	Jun. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Statement of Comprehensive Income [Abstract]
Other comprehensive income (loss)	$ (333)	$ 149	$ 584	$ (1,018)	$ 1,284

Amount after tax of other comprehensive income (loss) attributable to parent entity.

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