Note 12 - Hedging Activities (Details Textual) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Derivative, Notional Amount	$ 13,938		$ 14,740
Foreign Currency Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months	41
Other Comprehensive Income (Loss), Cash Flow Hedge, Reclassification for Discontinuance, before Tax	14	$ 14
New Investment Hedges [Member] \| Cash Flow Hedging [Member]
Derivative, Notional Amount	751		1,100
Foreign Exchange Forward [Member] \| Cash Flow Hedging [Member] \| Designated as Hedging Instrument [Member]
Derivative, Notional Amount	$ 751		892
Foreign Exchange Forward [Member] \| Net Investment Hedging [Member] \| Designated as Hedging Instrument [Member]
Derivative, Notional Amount			$ 251

Nominal or face amount used to calculate payment on derivative.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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The estimated net amount of unrealized gains or losses on foreign currency cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

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Amount, before tax, of reclassification from accumulated other comprehensive income (AOCI) for gain (loss) from discontinuance of cash flow hedge included in assessment of hedge effectiveness.

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