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Derivative Financial Instruments - Narrative (Details) | 3 Months Ended |
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Mar. 31, 2023 USD ($) counterparty | Dec. 31, 2022 USD ($)
Derivative [Line Items] |  |
Number of central counterparties | counterparty | 2 |
Notional value | $ 1,987,429,000 | $ 2,842,846,000
Derivative, fair value, amount offset against collateral, net | 11,000,000 | 12,000,000
Estimated accumulated other comprehensive income to be reclassified in next 12 months | 41,000,000 |
Cash collateral held relative to derivative exposure | 0 | 0
Cash collateral pledged | 13,000,000 | $ 11,000,000
CME |  |
Derivative [Line Items] |  |
Notional value | $ 1,800,000,000 |
Percent of total notional derivative contracts | 90.00% |
Amount of variation margin included as settlement | $ (47,000,000) |
LCH |  |
Derivative [Line Items] |  |
Notional value | $ 200,000,000 |
Percent of total notional derivative contracts | 10.00% |
Amount of variation margin included as settlement | $ (6,000,000) |

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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 https://asc.fasb.org/extlink&oid=121549185&loc=d3e80748-113994 + Details
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- Definition Amount of obligation to return cash collateral under master netting arrangements offset against derivative assets. + 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 (b) -URI https://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 5 -URI https://asc.fasb.org/extlink&oid=126966630&loc=d3e41228-113958 + Details
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- Definition The net amount as of the balance sheet date of the fair value of derivative assets and derivative liabilities that in accordance with the entity's accounting policy were offset against collateral under a master netting arrangement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=125515794&loc=d3e41678-113959 + Details
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