Derivative and Hedging Activities, Derivative Instruments Not Designated as Hedging Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Fair Value, Inputs, Level 3
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Derivatives (trading liabilities)	$ 430	$ 2,046
Fair Value, Inputs, Level 2 \| Interest rate-related instruments — customer and mirror \| Fair Value, Measurements, Recurring
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Derivative Asset	125,879	192,518
Derivatives (trading liabilities)	23,115	25,680
Fair Value, Inputs, Level 2 \| Commodity contracts \| Fair Value, Measurements, Recurring
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Derivative Asset	9,593	12,486
Derivatives (trading liabilities)	9,393	11,155
Asset
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Derivatives (trading and other assets), fair value	145,762	219,537
Less: Legally enforceable master netting agreements	1,456	1,936
Less: Cash collateral pledged/received	534	10,879
Derivative Asset	143,772	206,722
Liability
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Derivatives (trading and other liabilities), fair value	36,494	43,716
Less: Legally enforceable master netting agreements	1,456	1,936
Less: Cash collateral pledged/received	25,000	25,625
Derivatives (trading liabilities)	10,039	16,155
Not designated as hedging instruments \| Asset \| Interest rate-related instruments — customer and mirror
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	3,716,697	3,639,679
Not designated as hedging instruments \| Asset \| Foreign currency exchange forwards
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	476,479	411,292
Not designated as hedging instruments \| Asset \| Commodity contracts
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	33,320	87,547
Not designated as hedging instruments \| Asset \| Mortgage banking(a)
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	266,193	226,818
Not designated as hedging instruments \| Liability \| Interest rate-related instruments — customer and mirror
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	3,716,697	3,639,679
Not designated as hedging instruments \| Liability \| Foreign currency exchange forwards
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	465,165	398,890
Not designated as hedging instruments \| Liability \| Commodity contracts
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	33,519	83,214
Not designated as hedging instruments \| Liability \| Mortgage banking(a)
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	$ 397,000	$ 335,500

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

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