Derivatives - Derivatives on the Income Statement (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Not Designated as Hedging Instrument, Economic Hedge [Member]
Derivative [Line Items]
Amount of gain (loss) recognized in income on derivatives	$ 625	$ 1,605
Fair Value Hedging [Member] \| Designated as Hedging Instrument [Member]
Derivative [Line Items]
Amount of gain (loss) recognized in income on derivatives	10,136	12,052
Interest rate products [Member] \| Designated as Hedging Instrument [Member]
Derivative [Line Items]
Amount of (loss) recognized in income on hedged items	(10,515)	(11,917)
Interest rate products [Member] \| Not Designated as Hedging Instrument, Economic Hedge [Member] \| Other Non-Interest expense [Member]
Derivative [Line Items]
Amount of gain (loss) recognized in income on derivatives	273	122
Interest rate products [Member] \| Fair Value Hedging [Member] \| Designated as Hedging Instrument [Member] \| Interest income [Member]
Derivative [Line Items]
Amount of (loss) recognized in income on hedged items	(10,515)	(11,917)
Interest rate products [Member] \| Fair Value Hedging [Member] \| Designated as Hedging Instrument [Member] \| Other Non-Interest income [Member]
Derivative [Line Items]
Amount of gain (loss) recognized in income on derivatives	10,136	12,052
Forward Contracts [Member] \| Not Designated as Hedging Instrument, Economic Hedge [Member] \| Mortgage banking income [Member]
Derivative [Line Items]
Amount of gain (loss) recognized in income on derivatives	(800)	1,108
Interest Rate Lock Commitments [Member] \| Not Designated as Hedging Instrument, Economic Hedge [Member] \| Mortgage banking income [Member]
Derivative [Line Items]
Amount of gain (loss) recognized in income on derivatives	$ 1,152	$ 375

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
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- Definition

Total amount of gain (loss) derived from fair value hedges recognized in earnings in the period.

+ References

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-Section 50
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