Derivative and Hedging Activities, Derivative Instruments Not Designated as Hedging Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Asset
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Derivatives (trading and other assets), fair value	$ 293,583	$ 104,305
Less: Legally enforceable master netting agreements	1,586	10,410
Less: Cash collateral pledged/received	36,234	1,408
Derivative Asset	255,763	92,487
Liability
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Derivatives (trading and other liabilities), fair value	73,865	37,455
Less: Legally enforceable master netting agreements	1,586	10,410
Less: Cash collateral pledged/received	32,285	11,365
Derivatives (trading liabilities)	39,994	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	3,564,015	3,029,877
Derivatives (trading and other assets), fair value	238,003	77,024
Not designated as hedging instruments \| Asset \| Foreign currency exchange forwards
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	337,015	272,636
Derivatives (trading and other assets), fair value	4,200	4,226
Not designated as hedging instruments \| Asset \| Commodity contracts
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	163,307	255,089
Derivatives (trading and other assets), fair value	38,543	20,528
Not designated as hedging instruments \| Asset \| Mortgage banking(a)
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	299,330	255,291
Derivatives (trading and other assets), fair value	12,837	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	3,564,015	3,029,877
Derivatives (trading and other liabilities), fair value	31,472	13,073
Not designated as hedging instruments \| Liability \| Foreign currency exchange forwards
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	290,557	264,653
Derivatives (trading and other liabilities), fair value	4,102	4,048
Not designated as hedging instruments \| Liability \| Commodity contracts
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	158,756	255,165
Derivatives (trading and other liabilities), fair value	36,998	19,624
Not designated as hedging instruments \| Liability \| Mortgage banking(a)
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	393,184	263,000
Derivatives (trading and other liabilities), fair value	$ 1,293	$ 710

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

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