Derivatives (Notional and Fair Values) (Details) $ in Thousands	Dec. 31, 2017 USD ($) company	Dec. 31, 2016 USD ($)
Fair Values of Derivative Instruments
Derivative assets	$ 66,146	$ 83,780
Derivative liabilities	74,935	82,323
Derivative instruments designated as hedging instruments
Fair Values of Derivative Instruments
Notional Amount	35,811	131,391
Derivative assets	0	4,325
Derivative liabilities	6,799	5,976
Derivative instruments designated as hedging instruments \| Interest rate swaps on certificates of deposit
Fair Values of Derivative Instruments
Notional Amount	35,811	48,365
Derivative assets	0	0
Derivative liabilities	6,799	5,976
Derivative instruments designated as hedging instruments \| Foreign currency forward contracts
Fair Values of Derivative Instruments
Notional Amount	0	83,026
Derivative assets	0	4,325
Derivative liabilities	0	0
Derivative instruments not designated as hedging instruments
Fair Values of Derivative Instruments
Notional Amount	10,153,108	8,507,660
Derivative assets	66,146	79,455
Derivative liabilities	68,136	76,347
Derivative instruments not designated as hedging instruments \| Interest rate swaps and options
Fair Values of Derivative Instruments
Notional Amount	9,333,860	7,668,482
Derivative assets	58,633	67,578
Derivative liabilities	57,958	65,131
Derivative instruments not designated as hedging instruments \| Foreign exchange contracts
Fair Values of Derivative Instruments
Notional Amount	770,215	767,764
Derivative assets	5,840	11,874
Derivative liabilities	10,170	11,213
Derivative instruments not designated as hedging instruments \| Credit risk participation agreements (“RPAs”)
Fair Values of Derivative Instruments
Notional Amount	49,033	71,414
Derivative assets	1	3
Derivative liabilities	8	3
Derivative instruments not designated as hedging instruments \| Warrants
Fair Values of Derivative Instruments
Notional Amount	0	0
Derivative assets	1,672	0
Derivative liabilities	0	$ 0
Derivative instruments not designated as hedging instruments \| Public Companies
Fair Values of Derivative Instruments
Derivative assets	$ 993
Number of companies in which warrants are held \| company	4
Derivative instruments not designated as hedging instruments \| Private Companies
Fair Values of Derivative Instruments
Derivative assets	$ 679
Number of companies in which warrants are held \| company	23

Aggregate notional amount of derivative expressed in nonmonetary units. For example, the number of barrels specified in a fuel oil forward purchase contract.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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