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Derivatives - Fair Value of Derivative Contracts (Detail) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
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Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Derivative contracts, Assets |  | $ 931 | $ 1,868
Derivative contracts, Liabilities |  | 1,460 | 4,153
Notional Amounts | [1] | 6,933,793 | 11,776,260
FX/Commodities Options [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Derivative contracts, Assets |  | 74 | 26
Notional Amounts | [1] | 4,844 | 4,487
FX Swaps [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Derivative contracts, Assets |  | 562 | 1,278
Derivative contracts, Liabilities |  | 319 | 2,244
Notional Amounts | [1] | 513,588 | 555,519
Forwards [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Derivative contracts, Assets |  | 295 | 564
Derivative contracts, Liabilities |  | 215 | 1,285
Notional Amounts | [1] | 302,141 | 110,051
Futures [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Derivative contracts, Liabilities |  | 926 | 624
Notional Amounts | [1] | $ 6,113,220 | $ 11,106,203
[1] | Notional amounts represent the sum of gross long and short derivative contracts, an indication of the volume of the Company’s derivative activity, and do not represent anticipated losses.

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- Definition Fair value as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as a liability. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4B -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5624163-113959 + Details
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