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Contractual interest rate for funds borrowed, under the debt agreement.

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Fair value amount of debt instrument that was repurchased.

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Weighted average interest rate of debt outstanding.

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Financial Instruments - Long-Term Debt, Narrative (Details) $ in Millions, € in Billions	1 Months Ended		12 Months Ended
	Nov. 30, 2020 USD ($)	Jan. 31, 2019 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2021	Dec. 31, 2020	May 31, 2020 USD ($)	Mar. 31, 2020 USD ($)	Mar. 31, 2019 USD ($)	Jan. 31, 2019 EUR (€)
Debt Instrument [Line Items]
Loss on early retirement of debt			$ 138
Senior Unsecured Euro Debt, 5.75%, Due 2021 [Member]
Debt Instrument [Line Items]
Loss on early retirement of debt		$ 138
Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, face amount						$ 4,000	$ 1,250	$ 5,000
Weighted average interest rate						2.11%	2.67%	3.57%
Loss on early retirement of debt	$ 36
Senior Notes [Member] \| Senior Unsecured Debt, One Point Nine Five Percent, Due 2021 [Member]
Debt Instrument [Line Items]
Repurchased debt	$ 1,150
Stated interest rate	1.95%
Senior Notes [Member] \| Senior Unsecured Debt, Five Point Eight Zero Percent, Due 2023 [Member]
Debt Instrument [Line Items]
Repurchased debt	$ 342
Stated interest rate	5.80%
Senior Notes [Member] \| Senior Unsecured Euro Debt, 5.75%, Due 2021 [Member]
Debt Instrument [Line Items]
Repurchased debt		$ 1,300							€ 1.1
Stated interest rate		5.75%							5.75%
Redemption value		$ 1,500							€ 1.3
Unsecured Debt [Member]
Debt Instrument [Line Items]
Weighted average interest rate				1.00%	2.60%
Unsecured Debt [Member] \| Senior Notes Due 2047 [Member]
Debt Instrument [Line Items]
Repurchased debt							$ 1,065