Risk Management and Derivatives - Additional Information (Detail) - USD ($)	9 Months Ended
	Feb. 29, 2020	May 31, 2019
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Credit risk related contingent features collateral threshold	$ 50,000,000
Deferred net gains (net of tax) on both outstanding and matured derivatives accumulated in other comprehensive income are expected to be reclassified to net income during the next twelve months as a result of underlying hedged transactions also being recorded in net income	$ 322,000,000
Maximum term over which the Company is hedging exposures to the variability of cash flows for its forecasted and recorded transactions (in months)	23 months
Derivative instruments in net liability position	$ 1,000,000
Collateral received from counterparties to hedging instruments	86,000,000	$ 289,000,000
Not designated as derivative instrument
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total notional amount of outstanding derivatives	3,600,000,000
Embedded derivatives
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total notional amount of outstanding derivatives	$ 350,000,000
Derivatives designated as cash flow hedges
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Additional period for forecasted transaction expected to occur	2 years
Total notional amount of outstanding derivatives	$ 8,200,000,000
Cash and Cash Equivalents
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Collateral received from counterparties to hedging instruments	86,000,000
Cash and Cash Equivalents | Foreign exchange forwards and options
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Collateral received from counterparties to hedging instruments	$ 86,000,000	$ 289,000,000