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Commitments, Contingencies And Guarantees (Narrative) (Details) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 | Dec. 31, 2019
Notional amount of underlying swaps | $ 3,015,189 | $ 4,525,856
Financial Standby Letter of Credit [Member] |  |
Carrying value of the guarantee obligations, liability | 3,300 |
Commitments outstanding | 357,087 | $ 377,338
State Tax Credits [Member] |  |
Purchases of state tax credits | 151,200 |
Sales of state tax credits | 131,400 |
Outstanding purchase commitments expected to fund | 141,300 |
Risk Participation Agreement [Member] |  |
Carrying value of the guarantee obligations, liability | 701 |
Notional amount of underlying swaps | $ 288,700 |
Risk Participation Agreement [Member] | Minimum [Member] |  |
Risk Participation Agreements, Term | 2 years |
Risk Participation Agreement [Member] | Maximum [Member] |  |
Risk Participation Agreements, Term | 11 years |
Office Building |  |
Outstanding purchase commitments expected to fund | $ 106,600 |
Lessor, Operating Lease, Lease Not yet Commenced, Term of Contract | 15 years |
Anchor Tenant Percent of Building Leased | 40.00% |

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