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Derivative Instruments - Narrative (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Derivative [Line Items] |  |  |
Net unrealized gains (losses) arising during the period | $ (77,948) | $ 99,193 | $ (8,570)
Unrealized gain, after tax | (57,705) | 73,502 | $ (6,350)
Pre-tax income | 12,900 | 2,800 |
Unamortized deferred net loss balance from previously terminated cash flow hedges | 27,000 |  |
Pre-tax gains included in interest income on cash flow hedges | 4,000 |  |
Collateral | 64,500 | 155,400 |
Variation margin, amount reducing derivative liability | 94,600 | 162,700 |
Visa Derivative Liability | Level 3 | Fair Value, Measurements, Recurring |  |  |
Derivative [Line Items] |  |  |
Derivative, fair value adjustment | 2,700 | 890 |
Cash Flow Hedging |  |  |
Derivative [Line Items] |  |  |
Net unrealized gains (losses) arising during the period | 1,200 | 9,800 |
Unrealized gain, after tax | $ 930 | $ 7,300 |

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- Definition The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=121549185&loc=d3e80748-113994 + Details
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