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Derivatives - Narrative (Details) - USD ($) $ in Thousands |  | 3 Months Ended | 6 Months Ended |
--- | --- | --- | --- | ---
Nov. 01, 2019 | Jun. 30, 2020 | Jun. 30, 2019 | Mar. 31, 2017 | Mar. 31, 2016 | Jun. 30, 2020 | Jun. 30, 2019 | Dec. 31, 2019
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |  |  |
Collateral cash payables |  | $ 361,087 |  |  |  | $ 361,087 |  | $ 145,334
Total trading revenues |  | 100,300 | $ 54,500 |  |  | 178,600 | $ 99,000 |
Cash flow hedge length of time |  |  |  |  | 5 years |  |  |
Hedged amount of foreign currency denominated loans |  | 13,800 |  |  |  | 13,800 |  | 18,400
Derivative assets (Note 14) |  | 599,445 |  |  |  | 599,445 |  | 182,984
Derivative liability |  | 75,226 |  |  |  | 75,226 |  | 44,238
Cash Flow Hedge | Hedged Items |  |  |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |  |  |
Variability in cash flows related to debt instruments (primarily loans) |  |  |  |  | $ 250,000 |  |  |
Notional |  |  |  | $ 650,000 |  |  |  |
Derivative, expired during period |  |  |  |  |  | 200,000 |  |
Visa Class B Shares |  |  |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |  |  |
Derivative liabilities related to sale |  | 18,000 |  |  |  | 18,000 |  | 22,800
Additional Derivative Agreements | Derivative Instruments With Adjustable Collateral Posting Thresholds |  |  |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |  |  |
Net fair value of derivative assets with adjustable posting thresholds |  | 253,700 |  |  |  | 253,700 |  | 63,100
Net fair value of derivative liabilities with adjustable posting thresholds |  | 3,800 |  |  |  | 3,800 |  | 6,400
Collateral received |  | 340,000 |  |  |  | 340,000 |  | 148,500
Securities posted collateral |  | 43,500 |  |  |  | 43,500 |  | 18,400
Additional Derivative Agreements | Derivative Instruments With Accelerated Termination Provisions |  |  |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |  |  |
Net fair value of derivative assets with adjustable posting thresholds |  | 253,600 |  |  |  | 253,600 |  | 63,100
Net fair value of derivative liabilities with adjustable posting thresholds |  | 25,500 |  |  |  | 25,500 |  | 10,300
Collateral received |  | 340,000 |  |  |  | 340,000 |  | 148,500
Securities posted collateral |  | 65,100 |  |  |  | 65,100 |  | 22,700
Minimum | Cash Flow Hedge | Hedged Items |  |  |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |  |  |
Derivative, term of contract |  |  |  | 3 years |  |  |  |
Maximum | Cash Flow Hedge | Hedged Items |  |  |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |  |  |
Derivative, term of contract |  |  |  | 7 years |  |  |  |
Counterparties |  |  |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |  |  |
Collateral cash receivables |  | 230,200 |  |  |  | 230,200 |  | 136,600
Collateral cash payables |  | 130,600 |  |  |  | 130,600 |  | 53,000
Senior Subordinated Notes | Senior Debt Maturing In December 2019 |  |  |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |  |  |
Term borrowings |  | 400,000 |  |  |  | 400,000 |  |
Debt redeemed | $ 400,000 |  |  |  |  |  |  |
Senior Subordinated Notes | Senior Debt Maturing In December 2020 |  |  |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |  |  |
Term borrowings |  | 500,000 |  |  |  | 500,000 |  |
Derivatives, interest rate contracts |  |  |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |  |  |
Collateral cash payables |  | 348,497 |  |  |  | 348,497 |  | 143,334
Derivative assets (Note 14) |  | 564,037 |  |  |  | 564,037 |  | 162,344
Derivative liability |  | 44,743 |  |  |  | 44,743 |  | 24,431
Derivatives, interest rate contracts | Cash Flow Hedge | Hedged Items |  |  |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |  |  |
Variability in cash flows related to debt instruments (primarily loans) |  | 700,000 |  |  |  | 700,000 |  | $ 900,000
Credit Risk Contract |  |  |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |  |  |
Derivative asset, notional amount |  | 93,800 |  |  |  | 93,800 |  |
Derivative liability, notional amount |  | 246,100 |  |  |  | 246,100 |  |
Derivative assets (Note 14) |  | 170 |  |  |  | 170 |  |
Derivative liability |  | $ 830 |  |  |  | $ 830 |  |

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