Debt Obligations and Commitments - Additional Information (Detail) € in Millions, $ in Millions, R in Billions	Sep. 05, 2020 USD ($)	Sep. 05, 2020 EUR (€)	Sep. 05, 2020 ZAR (R)
Notes Due 2023 [Member] | Zero Point Seven Five Percent Notes Due 2023 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 1,000
Debt Instrument, Interest Rate, Stated Percentage	0.75%	0.75%	0.75%
Notes Due 2024 [Member] | Zero Point Two Five Percent Notes Due 2024 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount | €		€ 1,000
Debt Instrument, Interest Rate, Stated Percentage	0.25%	0.25%	0.25%
Notes Due 2025 [Member] | Two Point Two Five Percent Notes Due 2025 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 1,500
Debt Instrument, Interest Rate, Stated Percentage	2.25%	2.25%	2.25%
Notes Due 2027 [Member] | Two Point Six Two Five Percent Notes Due 2027 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 500
Debt Instrument, Interest Rate, Stated Percentage	2.625%	2.625%	2.625%
Notes Due 2028 [Member] | Zero Point Five Percent Notes Due 2028 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount | €		€ 1,000
Debt Instrument, Interest Rate, Stated Percentage	0.50%	0.50%	0.50%
Notes Due 2030 [Member] | Two Point Seven Five Percent Notes Due 2030 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 1,500
Debt Instrument, Interest Rate, Stated Percentage	2.75%	2.75%	2.75%
Notes Due 2030 [Member] | One Point Six Two Five Percent Notes Due 2030 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 1,000
Debt Instrument, Interest Rate, Stated Percentage	1.625%	1.625%	1.625%
Notes Due 2040 [Member] | Three Point Five Percent Notes Due 2040 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 750
Debt Instrument, Interest Rate, Stated Percentage	3.50%	3.50%	3.50%
Notes Due 2050 [Member] | Three Point Six Two Five Percent Notes Due 2050 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 1,500
Debt Instrument, Interest Rate, Stated Percentage	3.625%	3.625%	3.625%
Notes Due 2060 [Member] | Three Point Eight Seven Five Percent Notes Due 2060 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 750
Debt Instrument, Interest Rate, Stated Percentage	3.875%	3.875%	3.875%
Pioneer Bridge Loan Facilities [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Fair Value of Amount Outstanding	$ 1,300		R 21.7