Derivative and Hedging Activities, Derivative Instruments Not Designated as Hedging Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Asset
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Derivatives (trading and other assets), fair value	$ 131,061	$ 91,260
Less: Legally enforceable master netting agreements	4,629	5,322
Less: Cash collateral pledged/received	16,182	27,593
Derivative Asset	110,250	58,345
Liability
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Derivatives (trading and other liabilities), fair value	45,770	89,889
Less: Legally enforceable master netting agreements	4,629	5,322
Less: Cash collateral pledged/received	14,680	63
Derivatives (trading liabilities)	26,461	84,504
Designated as hedging instruments
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	500,000
Designated as hedging instruments \| Asset \| Interest rate-related instruments
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	500,000	0
Derivatives (trading and other assets), fair value	114	0
Designated as hedging instruments \| Liability \| Interest rate-related instruments
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	0	500,000
Derivatives (trading and other liabilities), fair value	0	40
Not designated as hedging instruments \| Asset
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Derivatives (trading and other assets), fair value	130,947	91,260
Not designated as hedging instruments \| Asset \| Interest rate-related instruments — customer and mirror
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	2,799,863	2,707,204
Derivatives (trading and other assets), fair value	100,376	52,796
Not designated as hedging instruments \| Asset \| Foreign currency exchange forwards
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	211,475	117,879
Derivatives (trading and other assets), fair value	3,153	721
Not designated as hedging instruments \| Asset \| Commodity contracts
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	259,210	331,727
Derivatives (trading and other assets), fair value	25,388	35,426
Not designated as hedging instruments \| Asset \| Interest rate lock commitments (mortgage)
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	300,515	191,222
Derivatives (trading and other assets), fair value	2,017	2,208
Not designated as hedging instruments \| Asset \| Time deposits
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	518	11,185
Derivatives (trading and other assets), fair value	13	109
Not designated as hedging instruments \| Liability
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Derivatives (trading and other liabilities), fair value	45,770	89,849
Not designated as hedging instruments \| Liability \| Interest rate-related instruments — customer and mirror
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	2,799,863	2,707,204
Derivatives (trading and other liabilities), fair value	17,586	52,653
Not designated as hedging instruments \| Liability \| Foreign currency exchange forwards
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	184,476	69,153
Derivatives (trading and other liabilities), fair value	2,823	675
Not designated as hedging instruments \| Liability \| Commodity contracts
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	258,483	315,861
Derivatives (trading and other liabilities), fair value	24,758	34,340
Not designated as hedging instruments \| Liability \| Interest rate lock commitments (mortgage)
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	227,060	139,984
Derivatives (trading and other liabilities), fair value	590	2,072
Not designated as hedging instruments \| Liability \| Time deposits
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	518	11,185
Derivatives (trading and other liabilities), fair value	$ 13	$ 109

Amount of obligation to return cash collateral under master netting arrangements offset against derivative assets.

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Fair value of liability associated with financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset.

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