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Derivatives - Derivatives Associated With Interest Rate Risk Management Activities (Details) - USD ($) $ in Thousands | Sep. 30, 2020 | Dec. 31, 2019
--- | --- | ---
Customer interest rate contracts |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Notional | $ 3,847,085 | $ 2,697,522
Assets | 240,218 | 65,768
Liabilities | 2,444 | 6,858
Offsetting upstream interest rate contracts |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Notional | 3,847,085 | 2,697,522
Assets | 2,317 | 2,583
Liabilities | 16,828 | 3,994
Customer Interest Rate Contracts Hedging | Hedging Instruments And Hedged Items | Customer interest rate contracts |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Notional | 6,667,600 | 3,044,067
Assets | 487,005 | 90,394
Liabilities | 303 | 3,515
Customer Interest Rate Contracts Hedging | Hedging Instruments And Hedged Items | Offsetting upstream interest rate contracts |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Notional | 6,667,600 | 3,044,067
Assets | 303 | 3,537
Liabilities | 25,997 | 9,735
Debt Hedging | Hedging Instruments And Hedged Items | Interest Rate Swap |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Notional | 500,000 | 500,000
Assets | 13 |
Liabilities |  | 69
Debt Hedging | Hedging Instruments And Hedged Items | Term Borrowings, Par |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Term borrowings | 500,000 | 500,000
Debt Hedging | Hedging Instruments And Hedged Items | Term Borrowings, Cumulative Fair Value Hedging Adjustments |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Term borrowings | 729 | (1,604)
Debt Hedging | Hedging Instruments And Hedged Items | Term Borrowings, Unamortized Premium (Discount) and Issuance Costs |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Term borrowings | (74) | (740)
Debt Hedging | Hedging Instruments And Hedged Items | Term Borrowings |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Term borrowings | $ 500,655 | $ 497,656

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- Definition Nominal or face amount used to calculate payment on derivative. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5580258-113959 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959 + Details
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- Definition Fair value as of the balance sheet date of interest rate derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets. + References No definition available. + Details
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