Derivative Financial Instruments - Outstanding Foreign Currency Forward Contracts (Detail) ₽ in Millions, € in Millions, ₩ in Millions, ¥ in Millions, £ in Millions, kr in Millions, kr in Millions, R$ in Millions, R in Millions, $ in Millions, $ in Millions, $ in Millions, $ in Millions	Dec. 31, 2020 USD ($)	Dec. 31, 2020 KRW (₩)	Dec. 31, 2020 NOK (kr)	Dec. 31, 2020 RUB (₽)	Dec. 31, 2020 DKK (kr)	Dec. 31, 2020 BRL (R$)	Dec. 31, 2020 MXN ($)	Dec. 31, 2020 JPY (¥)	Dec. 31, 2020 ZAR (R)	Dec. 31, 2020 EUR (€)	Dec. 31, 2020 SGD ($)	Dec. 31, 2020 GBP (£)	Dec. 31, 2020 CAD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2019 KRW (₩)	Dec. 31, 2019 NOK (kr)	Dec. 31, 2019 RUB (₽)	Dec. 31, 2019 DKK (kr)	Dec. 31, 2019 MXN ($)	Dec. 31, 2019 JPY (¥)	Dec. 31, 2019 ZAR (R)	Dec. 31, 2019 EUR (€)	Dec. 31, 2019 SGD ($)	Dec. 31, 2019 GBP (£)	Dec. 31, 2019 CAD ($)
Forward Contracts [Member]
Derivative [Line Items]
Foreign currency, Cash flow hedging	$ 367	₩ 17,600	kr 3,817	₽ 1,118	kr 875	R$ 768	$ 402	¥ 340	R 124	€ 116	$ 31	£ 18	$ 1	$ 686	₩ 17,600	kr 5,377	₽ 1,012	kr 21	$ 115	¥ 36	R 124	€ 188	$ 42	£ 20	$ 3