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Employee Benefit Plans (Summary of Changes in the Corporation's Qualified Defined Benefit Pension Plan's Level 3 Investments Measured at Fair Value on a Recurring Basis) (Details) - Private placements - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020
Balance at beginning of period | $ 58 | $ 57
Net Gains (Losses) Realized | 2 | 1
Net Gains (Losses) Unrealized | (4) | 3
Purchases | 44 | 57
Sales | (50) | (60)
Balance at end of period | $ 50 | $ 58

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- Definition This element represents total realized gains or losses for the period, arising from assets measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in earnings or resulted in a change in net asset value. + References No definition available. + Details
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- Definition This element represents total unrealized gains or losses for the period, arising from assets measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in earnings or resulted in a change in net asset value. + References No definition available. + Details
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- Definition Sales + References No definition available. + Details
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- Details
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Balance Type: |
Period Type: |