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Derivatives - Summary of Gains and Losses on Derivative Contracts (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (loss), net on derivative contract	$ 14,629	$ 32,287	$ 23,090
FX/Commodities Options [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (loss), net on derivative contract	252	14,657	12,852
FX Swaps [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (loss), net on derivative contract	2,340	1,271	1,332
Equity Options [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (loss), net on derivative contract	318	102	591
Interest Rate Swaps [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (loss), net on derivative contract		(5)	47
Futures [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (loss), net on derivative contract	15,316	16,484	8,306
Forwards [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (loss), net on derivative contract	$ (3,597)	$ (222)	$ (38)

X

- Definition

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5618551-113959

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