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v3.19.3.a.u2

Summary Of Significant Accounting Policies New Accounting Pronouncements (Narrative) (Details) - Adjustments for New Accounting Pronouncement [Member] $ in Billions | 12 Months Ended
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Dec. 31, 2019 USD ($)
Loans Receivable and related Allowance for Credit Losses [Member] |
Item Effected [Line Items] |
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification | $ 2.5
Allowance for Credit Losses [Member] |
Item Effected [Line Items] |
Write Off Policy Cap Percentage Based On Future Cash Flows | 200.00%
Minimum [Member] | Annual Net Income Impact [Member] |
Item Effected [Line Items] |
New Accounting Pronouncement Estimated Impact | 30.00%
Minimum [Member] | Quarterly Net Income Impact [Member] |
Item Effected [Line Items] |
New Accounting Pronouncement Estimated Impact | 50.00%
Minimum [Member] | Allowance for Credit Losses [Member] |
Item Effected [Line Items] |
New Accounting Pronouncement Estimated Impact | 12.00%
Maximum [Member] | Annual Net Income Impact [Member] |
Item Effected [Line Items] |
New Accounting Pronouncement Estimated Impact | 60.00%
Maximum [Member] | Quarterly Net Income Impact [Member] |
Item Effected [Line Items] |
New Accounting Pronouncement Estimated Impact | 80.00%
Maximum [Member] | Allowance for Credit Losses [Member] |
Item Effected [Line Items] |
New Accounting Pronouncement Estimated Impact | 15.00%

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