Derivative and Hedging Activities, Derivative Instruments Not Designated as Hedging Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Asset
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Derivatives (trading and other assets), fair value	$ 311,413	$ 104,305
Less: Legally enforceable master netting agreements	2,847	10,410
Less: Cash collateral pledged/received	69,654	1,408
Derivative Asset	238,912	92,487
Liability
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Derivatives (trading and other liabilities), fair value	118,228	37,455
Less: Legally enforceable master netting agreements	2,847	10,410
Less: Cash collateral pledged/received	30,645	11,365
Derivatives (trading liabilities)	84,736	15,680
Not designated as hedging instruments \| Asset \| Interest rate-related instruments — customer and mirror
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	3,430,859	3,029,877
Derivatives (trading and other assets), fair value	220,445	77,024
Not designated as hedging instruments \| Asset \| Foreign currency exchange forwards
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	322,066	272,636
Derivatives (trading and other assets), fair value	9,272	4,226
Not designated as hedging instruments \| Asset \| Commodity contracts
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	208,621	255,089
Derivatives (trading and other assets), fair value	69,241	20,528
Not designated as hedging instruments \| Asset \| Mortgage banking(a)
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	343,193	255,291
Derivatives (trading and other assets), fair value	12,454	2,527
Not designated as hedging instruments \| Liability \| Interest rate-related instruments — customer and mirror
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	3,430,859	3,029,877
Derivatives (trading and other liabilities), fair value	30,449	13,073
Not designated as hedging instruments \| Liability \| Foreign currency exchange forwards
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	295,774	264,653
Derivatives (trading and other liabilities), fair value	9,215	4,048
Not designated as hedging instruments \| Liability \| Commodity contracts
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	203,955	255,165
Derivatives (trading and other liabilities), fair value	67,592	19,624
Not designated as hedging instruments \| Liability \| Mortgage banking(a)
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	471,000	263,000
Derivatives (trading and other liabilities), fair value	$ 10,972	$ 710

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

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