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Derivative Financial Instruments - Additional Information (Details) - USD ($) $ in Thousands | 12 Months Ended |
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Dec. 31, 2018 | Dec. 31, 2017
Derivative [Line Items] |  |
Total amount of notional derivative contracts | $ 6,000,000 |
Net positive exposure | 27,000 | $ 20,000
Estimated reclassification of AOCI to interest expense | 5,500 |
Cash collateral pledged | 27,200 | 21,600
CME |  |
Derivative [Line Items] |  |
Total amount of notional derivative contracts | $ 5,400,000 |
Percentage of total notional derivative contracts | 90.20% |
Amount of variation margin included as settlement | $ (16,700) |
LCH |  |
Derivative [Line Items] |  |
Total amount of notional derivative contracts | $ 600,000 |
Percentage of total notional derivative contracts | 9.80% |
Amount of variation margin included as settlement | $ (6,100) |
Interest Rate Swaps |  |
Derivative [Line Items] |  |
Total amount of notional derivative contracts | 5,996,310 | 5,459,075
Fair Value | Interest Rate Swaps | Designated as Hedging Instrument |  |
Derivative [Line Items] |  |
Total amount of notional derivative contracts | $ 3,137,965 | $ 3,062,849

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- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + Details
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- Definition Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958 + Details
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- Definition Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226016-175313 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109980867&loc=d3e41678-113959 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (d)(2) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 + Details
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- Definition The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve 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=112277219&loc=d3e80748-113994 + Details
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