CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Feb. 28, 2019	Feb. 28, 2018	Feb. 28, 2019	Feb. 28, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net income (loss)	$ 2,745	$ (4,047)	$ 7,343	$ 311
Other comprehensive income (loss), net of tax:
Net foreign currency translation gains (losses)	10	43	(148)	51
Net unrealized gains on defined benefit plans	6	8	19	26
Net unrealized gains (losses) on marketable securities	233	(439)	120	(567)
Net unrealized (losses) gains on cash flow hedges	(18)	6	(36)	19
Total other comprehensive income (loss), net	231	(382)	(45)	(471)
Comprehensive income (loss)	$ 2,976	$ (4,429)	$ 7,298	$ (160)

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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