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Financial Instruments (Narrative) (Details) € in Millions, ¥ in Millions, £ in Millions, SFr in Millions	12 Months Ended
	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2019 JPY (¥)	Dec. 31, 2019 EUR (€)	Dec. 31, 2019 GBP (£)	Dec. 31, 2019 CHF (SFr)
Derivative [Line Items]
Average remaining maturity of foreign currency derivatives	12 months
Maximum remaining maturity of foreign currency derivatives	30 days
Foreign currency-denominated notes, designated as hedge	$ 4,100,000,000	$ 2,650,000,000
Variable rate	11.00%			11.00%	11.00%	11.00%	11.00%
Losses expected to be reclassified in the next 12 months	$ 16,300,000
Unrealized losses from equity securities	395,300,000	(20,100,000)
Other-than-temporary impairment losses recognized during the year	$ 0	0	$ 0
Percentage of nonperforming assets	56.00%
Accounts receivable derecognized	$ 678,800,000	696,200,000
Buy USD Sell Euro
Derivative [Line Items]
Derivative liability, notional amount	447,900,000
Derivative asset, notional amount \| €					€ 402.9
Buy Euro Sell USD
Derivative [Line Items]
Derivative liability, notional amount \| €					€ 1,810.0
Derivative asset, notional amount	2,020,000,000.00
Buy USD Sell Japanese Yen
Derivative [Line Items]
Derivative liability, notional amount	308,300,000
Derivative asset, notional amount \| ¥				¥ 33,490
Buy Swiss Francs Sell USD
Derivative [Line Items]
Derivative liability, notional amount \| SFr							SFr 101.4
Derivative asset, notional amount	103,500,000
Buy GBP Sell USD
Derivative [Line Items]
Derivative liability, notional amount \| £						£ 236.2
Derivative asset, notional amount	310,900,000
Currency Swap
Derivative [Line Items]
Derivative liability, notional amount	1,450,000,000
Swap Swiss Francs to USD
Derivative [Line Items]
Derivative liability, notional amount	1,000,000,000.00
Forward-starting interest rate swaps
Derivative [Line Items]
Derivative asset, notional amount	396,000,000.0
Foreign Currency Denominated Debt
Derivative [Line Items]
Long-term debt	5,490,000,000	$ 3,400,000,000
Cash flow hedges \| Designated as Hedging Instrument \| Forward-starting interest rate swaps
Derivative [Line Items]
Derivative, notional amount	$ 1,000,000,000.00