Summary of Impact of Derivative Financial Instruments to Condensed Consolidated Statements of Operations (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Derivative [Line Items]
Realized Gains (Losses)	$ (15,479)	$ 10,155
Net Change in Unrealized Gain (Loss)	8,380	(14,692)
Net Investment Hedges \| Foreign Currency Contracts
Derivative [Line Items]
Realized Gains (Losses)	129	240
Freestanding Derivatives \| Credit Default Swap
Derivative [Line Items]
Realized Gains (Losses)	(3,811)	1,826
Net Change in Unrealized Gain (Loss)	(4,276)	(2,922)
Freestanding Derivatives \| Foreign Currency Contracts
Derivative [Line Items]
Realized Gains (Losses)	(4,310)	12,064
Net Change in Unrealized Gain (Loss)	15,322	(11,024)
Freestanding Derivatives \| Interest Rate Contracts
Derivative [Line Items]
Realized Gains (Losses)	(7,358)	(3,735)
Net Change in Unrealized Gain (Loss)	$ (2,666)	$ (746)

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- Definition

The difference between the book value and the sale price of options, swaps, futures, forward contracts, and other derivative instruments. This element refers to the gain (loss) included in earnings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.13(h))
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

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- Definition

The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

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