Derivatives and Hedging Activity - Effect on Financial Statements (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Derivatives
Gain on derivative financial instruments, net	$ 70,734	$ 21,598	$ 20,451
Derivatives not designated as hedging instruments
Derivatives
Gain on derivative financial instruments, net	70,734	21,598	20,451
Interest rate swaps caps \| Derivatives not designated as hedging instruments
Derivatives
Gain on derivative financial instruments, net	21,741	(22,675)	(15,662)
Foreign exchange contracts \| Derivatives not designated as hedging instruments
Derivatives
Gain on derivative financial instruments, net	51,818	44,089	37,207
Credit index instruments \| Derivatives not designated as hedging instruments
Derivatives
Gain on derivative financial instruments, net	(2,825)	184	(1,094)
Cash flow hedges \| Interest rate swaps
Derivatives
Gain (Loss) Recognized in OCI (effective portion)	(284)	(709)	(865)
Gain (Loss) Reclassified from AOCI into Income (effective portion)	$ (323)	$ (741)	$ (1,372)

The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4D
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624177-113959

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- Definition

The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

+ References

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+ References

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Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5618551-113959

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