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Derivative Financial Instruments - Summary of Interest Rate Swaps Designated as Fair Value Hedges (Detail) - USD ($) | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019
Derivative Instruments, Gain (Loss) [Line Items] |  |
Notional amounts | $ 1,452,000,000 | $ 665,500,000
Fixed Interest Swap | Fair Value Hedging | Derivatives designated as hedging instruments |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Notional amounts | $ 726,516,000 | $ 130,500,000
Weighted average pay rates | 0.63% | 1.82%
Weighted average receive rates | 1.23% | 2.20%
Weighted average maturity (in years) | 6 years 10 months 24 days | 2 years 9 months 18 days
Fair value of swaps | $ 9,766,000 | $ 1,555,000

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- Definition Average remaining period until maturity of the derivative contract, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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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 all interest rate derivatives designated as cash flow hedging 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=117331979&loc=d3e41228-113958 + Details
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