Derivatives - Schedule of Gain (Loss) in Consolidated Statements of Income Related to Derivative Instruments (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Derivatives Designated as Hedging Instruments \| Cash Flow Hedges \| Commercial Loans \| Interest Rate Swaps
Derivative Instruments Gain Loss [Line Items]
OCI	$ 6,646	$ (11,278)
Reclassified from AOCI to interest income	(1,508)	(333)
Derivatives Designated as Hedging Instruments \| Cash Flow Hedges \| Commercial Loans \| Interest Rate Collars
Derivative Instruments Gain Loss [Line Items]
OCI	41,477
Derivatives Not Designated as Hedging Instruments \| Mortgage Loan Held for Sale Interest Rate Lock Commitments
Derivative Instruments Gain Loss [Line Items]
Noninterest income	69	61
Derivatives Not Designated as Hedging Instruments \| Foreign Exchange Contracts
Derivative Instruments Gain Loss [Line Items]
Noninterest income	$ 1,140	$ 508

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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=84234895&loc=SL5618551-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (a),(c),(d),(e)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

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- Definition

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

+ References

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=84234895&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=84234895&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.

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