Financial Instruments - Derivatives (Details) € in Millions, ₩ in Millions, ¥ in Millions, ¥ in Millions, £ in Millions, kr in Millions, $ in Millions, $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2020 KRW (₩) t	Dec. 31, 2019 KRW (₩) t	Mar. 31, 2020 USD ($)	Mar. 31, 2020 JPY (¥)	Mar. 31, 2020 MXN ($)	Mar. 31, 2020 CNY (¥)	Mar. 31, 2020 SEK (kr)	Mar. 31, 2020 EUR (€)	Mar. 31, 2020 GBP (£)	Dec. 31, 2019 USD ($)	Dec. 31, 2019 JPY (¥)	Dec. 31, 2019 MXN ($)	Dec. 31, 2019 CNY (¥)	Dec. 31, 2019 SEK (kr)	Dec. 31, 2019 EUR (€)	Dec. 31, 2019 GBP (£)
Derivative [Line Items]
Swaption contract notional amount			$ 750
Accumulated other comprehensive income (loss), cumulative changes in net gain (loss) from hedges, before tax			46							$ 4
Swaption
Derivative [Line Items]
Accumulated other comprehensive income (loss), cumulative changes in net gain (loss) from hedges, before tax			1							0
Foreign currency
Derivative [Line Items]
Accumulated other comprehensive income (loss), cumulative changes in net gain (loss) from hedges, before tax			(3)							0
Commodity contracts | Maturity July 2020
Derivative [Line Items]
Copper notional amount (mass) | t	148	203
Brazil, Brazil Real | Foreign currency | Maturity March 2020
Derivative [Line Items]
Foreign currency notional amount | €								€ 0							€ 1
United Kingdom, Pounds | Foreign currency | Maturity March 2020
Derivative [Line Items]
Foreign currency notional amount			0					0		4					9
China, Yuan Renminbi | Foreign currency | Maturity December 2020
Derivative [Line Items]
Foreign currency notional amount			5							2
Euro Member Countries, Euro | Cross currency interest rate contract | Maturity March 2025
Derivative [Line Items]
Foreign currency notional amount | €								450
Euro Member Countries, Euro | Foreign currency | Maturity October 2020
Derivative [Line Items]
Foreign currency notional amount | ¥						¥ 22							¥ 0
Euro Member Countries, Euro | Foreign currency | Maturity December 2020
Derivative [Line Items]
Foreign currency notional amount			11	¥ 290			kr 165			18	¥ 383			kr 0
Euro Member Countries, Euro | Foreign currency | Maturity January 2021
Derivative [Line Items]
Foreign currency notional amount | £									£ 2							£ 0
India, Rupees | Foreign currency | Maturity May 2020
Derivative [Line Items]
Foreign currency notional amount			3							0
India, Rupees | Foreign currency | Maturity July 2020
Derivative [Line Items]
Foreign currency notional amount			78							0
Japan, Yen | Cross currency interest rate contract | Maturity February 2023
Derivative [Line Items]
Foreign currency notional amount | ¥				10,978
Japan, Yen | Foreign currency | Maturity July 2020
Derivative [Line Items]
Foreign currency notional amount			1			¥ 26				0			¥ 0
Japan, Yen | Foreign currency | Maturity December 2020
Derivative [Line Items]
Foreign currency notional amount | ₩	₩ 3,705	₩ 0
Korea (South), Won | Foreign currency | Maturity December 2020
Derivative [Line Items]
Foreign currency notional amount			38	¥ 530				10		4	¥ 409				13
Sweden, Krona | Foreign currency | Maturity January 2020
Derivative [Line Items]
Foreign currency notional amount | €								0							3
United States of America, Dollars | Cross currency interest rate contract | Maturity February 2023
Derivative [Line Items]
Foreign currency notional amount			100
United States of America, Dollars | Cross currency interest rate contract | Maturity March 2025
Derivative [Line Items]
Foreign currency notional amount			500
United States of America, Dollars | Foreign currency | Maturity December 2020
Derivative [Line Items]
Foreign currency notional amount | €								€ 2							€ 14
United States of America, Dollars | Foreign currency | Maturity March 2021
Derivative [Line Items]
Foreign currency notional amount					$ 380							$ 0
Net investment hedge | Cross currency interest rate contract
Derivative [Line Items]
Accumulated other comprehensive income (loss), cumulative changes in net gain (loss) from hedges, before tax			51							16
Net investment hedge | Foreign currency
Derivative [Line Items]
Accumulated other comprehensive income (loss), cumulative changes in net gain (loss) from hedges, before tax			$ 6							$ 5