Derivative Financial Instruments - Notional Amounts and Fair Values (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Interest rate swaps
Notional amounts and fair values of derivatives
Financial instruments pledged as collateral	$ 12,100	$ 13,800
Cash pledged as collateral	18,300	15,600
Derivatives designated as hedging instruments \| Interest rate swaps
Notional amounts and fair values of derivatives
Notional Amount	200,504	232,867
Derivatives designated as hedging instruments \| Interest rate swaps \| Other liabilities
Notional amounts and fair values of derivatives
Liability Derivatives	(5,296)	(8,996)
Derivatives Not Designated as Hedging Instruments \| Interest rate swaps
Notional amounts and fair values of derivatives
Notional Amount	1,297,101	682,621
Asset Derivatives	16,000	10,900
Liability Derivatives	(18,300)	(14,100)
Derivatives Not Designated as Hedging Instruments \| Interest rate swaps \| Other assets
Notional amounts and fair values of derivatives
Asset Derivatives	15,982	10,909
Derivatives Not Designated as Hedging Instruments \| Interest rate swaps \| Other liabilities
Notional amounts and fair values of derivatives
Liability Derivatives	(18,299)	(14,126)
Derivatives Not Designated as Hedging Instruments \| Funding Swap (Visa Derivative)
Notional amounts and fair values of derivatives
Notional Amount	37,143
Liability Derivatives	(7,500)
Derivatives Not Designated as Hedging Instruments \| Funding Swap (Visa Derivative) \| Other liabilities
Notional amounts and fair values of derivatives
Liability Derivatives	(7,460)
Derivatives Not Designated as Hedging Instruments \| Foreign exchange contracts
Notional amounts and fair values of derivatives
Notional Amount	3,664	4,821
Derivatives Not Designated as Hedging Instruments \| Foreign exchange contracts \| Other assets
Notional amounts and fair values of derivatives
Asset Derivatives		$ 93
Derivatives Not Designated as Hedging Instruments \| Foreign exchange contracts \| Other liabilities
Notional amounts and fair values of derivatives
Liability Derivatives	$ (147)

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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 (c)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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