Derivative Financial Instruments (Assets and liabilities) (Details 2) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018
Derivative Financial Instruments Not Designated as Hedging Instruments
Document Period End Date	Jun. 30, 2019
Asset Derivatives	$ 27,869	$ 14,604
Liability Derivatives	8,292	9,747
Interest Rate Lock Commitments
Derivative Financial Instruments Not Designated as Hedging Instruments
Asset Derivatives	2,143	877
Liability Derivatives	0	6
Forward Commitments
Derivative Financial Instruments Not Designated as Hedging Instruments
Asset Derivatives	0	4
Liability Derivatives	800	356
Interest Rate Swap Agreements
Derivative Financial Instruments Not Designated as Hedging Instruments
Asset Derivatives	25,228	12,915
Liability Derivatives	7,415	9,370
Foreign Exchange Contracts
Derivative Financial Instruments Not Designated as Hedging Instruments
Asset Derivatives	498	808
Liability Derivatives	$ 77	$ 15
Visa Conversion Rate Swap Agreement
Derivative Financial Instruments Not Designated as Hedging Instruments
Liability Derivatives			$ 1,000

The end date of the period reflected on the cover page if a periodic report. For all other reports and registration statements containing historical data, it is the date up through which that historical data is presented. If there is no historical data in the report, use the filing date. The format of the date is CCYY-MM-DD.

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- Definition

Fair value as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as an asset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624163-113959

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- Definition

Fair value as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as a liability.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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