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Derivatives (Derivatives Not Designated as Hedging Instruments - Interest Rate Contracts) (Details) - USD ($) $ in Thousands | Sep. 30, 2019 | Dec. 31, 2018
--- | --- | ---
Derivative [Line Items] |  |
Derivative assets - Fair value | $ 358,639 | $ 107,816
Derivative liabilities - Fair value | 263,734 | 118,305
Derivatives not designated as hedging instruments |  |
Derivative [Line Items] |  |
Notional amount | 18,988,712 | 15,222,341
Derivative assets - Fair value | 358,639 | 107,816
Derivative liabilities - Fair value | 260,499 | 111,828
Derivatives not designated as hedging instruments | Interest rate contracts |  |
Derivative [Line Items] |  |
Notional amount | 14,139,233 | 11,695,499
Derivative assets - Fair value | 264,603 | 69,818
Derivative liabilities - Fair value | 168,113 | 69,267
Derivatives not designated as hedging instruments | Financial Counterparty | Interest rate contracts |  |
Derivative [Line Items] |  |
Notional amount | 7,070,000 | 5,850,000
Interest rate contracts | Derivatives not designated as hedging instruments | Customer Counterparty | Written options |  |
Derivative [Line Items] |  |
Notional amount | 1,009,823 | 931,601
Derivative assets - Fair value | 0 | 0
Derivative liabilities - Fair value | 59 | 492
Interest rate contracts | Derivatives not designated as hedging instruments | Customer Counterparty | Sold collars and corridors |  |
Derivative [Line Items] |  |
Notional amount | 495,511 | 429,879
Derivative assets - Fair value | 3,592 | 1,121
Derivative liabilities - Fair value | 6 | 305
Interest rate contracts | Derivatives not designated as hedging instruments | Customer Counterparty | Swaps |  |
Derivative [Line Items] |  |
Notional amount | 5,560,947 | 4,482,881
Derivative assets - Fair value | 260,251 | 41,457
Derivative liabilities - Fair value | 975 | 41,545
Interest rate contracts | Derivatives not designated as hedging instruments | Customer Counterparty | Interest rate contracts |  |
Derivative [Line Items] |  |
Notional amount | 7,066,281 | 5,844,361
Derivative assets - Fair value | 263,843 | 42,578
Derivative liabilities - Fair value | 1,040 | 42,342
Interest rate contracts | Derivatives not designated as hedging instruments | Financial Counterparty | Purchased options |  |
Derivative [Line Items] |  |
Notional amount | 1,009,823 | 931,601
Derivative assets - Fair value | 61 | 503
Derivative liabilities - Fair value | 0 | 0
Interest rate contracts | Derivatives not designated as hedging instruments | Financial Counterparty | Collars and corridors |  |
Derivative [Line Items] |  |
Notional amount | 495,511 | 429,879
Derivative assets - Fair value | 6 | 308
Derivative liabilities - Fair value | 3,641 | 1,140
Interest rate contracts | Derivatives not designated as hedging instruments | Financial Counterparty | Swaps |  |
Derivative [Line Items] |  |
Notional amount | 5,567,618 | 4,489,658
Derivative assets - Fair value | 693 | 26,429
Derivative liabilities - Fair value | 163,432 | 25,785
Interest rate contracts | Derivatives not designated as hedging instruments | Financial Counterparty | Interest rate contracts |  |
Derivative [Line Items] |  |
Notional amount | 7,072,952 | 5,851,138
Derivative assets - Fair value | 760 | 27,240
Derivative liabilities - Fair value | $ 167,073 | $ 26,925

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- Definition Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and elected not to be offset. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 + Details
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