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Derivatives (Narrative) (Details) - 3 months ended Mar. 31, 2021 $ in Millions | USD ($) | EUR (€)
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Derivative [Line Items] |  |
Net investment hedge, threshold percentage of the equity balance | 80.00% |
Decrease in net investment hedges | $ | $ 53 |
Net Investment Hedging |  |
Derivative [Line Items] |  |
Derivative, notional amount | € |  | € 1,100,000,000

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