Segment Information (Net Revenue By Geographic Area) (Details) - USD ($) $ in Millions	3 Months Ended
Jun. 30, 2021	Jun. 30, 2020
Revenue from External Customer [Line Items]
Net revenue	$ 1,551	$ 1,459
North America
Revenue from External Customer [Line Items]
Net revenue	682	627
International
Revenue from External Customer [Line Items]
Net revenue	$ 869	$ 832

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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+ Details