Derivative and Hedging Activities, Derivative Instruments Not Designated as Hedging Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Asset
Derivative Instruments Designated/Not Designated as Hedging Instruments
Derivatives (trading and other assets), fair value	$ 219,537	$ 104,305
Less: Legally enforceable master netting agreements	1,936	10,410
Less: Cash collateral pledged/received	10,879	1,408
Net Amounts Presented on the Consolidated Balance Sheets	206,722	92,487
Liability
Derivative Instruments Designated/Not Designated as Hedging Instruments
Derivatives (trading and other liabilities), fair value	43,716	37,455
Less: Legally enforceable master netting Liability	1,936	10,410
Less: Cash collateral pledged/received	25,625	11,365
Net Amounts Presented on the Consolidated Balance Sheets	16,155	15,680
Not designated as hedging instruments \| Asset \| Interest Rate Related Instruments Customer and Mirror
Derivative Instruments Designated/Not Designated as Hedging Instruments
Derivative Asset, Notional Amount	3,639,679	3,029,877
Derivatives (trading and other assets), fair value	192,518	77,024
Not designated as hedging instruments \| Asset \| Foreign currency exchange forwards
Derivative Instruments Designated/Not Designated as Hedging Instruments
Derivative Asset, Notional Amount	411,292	272,636
Derivatives (trading and other assets), fair value	4,909	4,226
Not designated as hedging instruments \| Asset \| Commodity contracts
Derivative Instruments Designated/Not Designated as Hedging Instruments
Derivative Asset, Notional Amount	87,547	255,089
Derivatives (trading and other assets), fair value	12,486	20,528
Not designated as hedging instruments \| Asset \| Mortgage banking(a)
Derivative Instruments Designated/Not Designated as Hedging Instruments
Derivative Asset, Notional Amount	226,818	255,291
Derivatives (trading and other assets), fair value	9,624	2,527
Not designated as hedging instruments \| Liability \| Interest Rate Related Instruments Customer and Mirror
Derivative Instruments Designated/Not Designated as Hedging Instruments
Derivative Liability, Notional Amount	3,639,679	3,029,877
Derivatives (trading and other liabilities), fair value	25,680	13,073
Not designated as hedging instruments \| Liability \| Foreign currency exchange forwards
Derivative Instruments Designated/Not Designated as Hedging Instruments
Derivative Liability, Notional Amount	398,890	264,653
Derivatives (trading and other liabilities), fair value	4,836	4,048
Not designated as hedging instruments \| Liability \| Commodity contracts
Derivative Instruments Designated/Not Designated as Hedging Instruments
Derivative Liability, Notional Amount	83,214	255,165
Derivatives (trading and other liabilities), fair value	11,155	19,624
Not designated as hedging instruments \| Liability \| Mortgage banking(a)
Derivative Instruments Designated/Not Designated as Hedging Instruments
Derivative Liability, Notional Amount	335,500	263,000
Derivatives (trading and other liabilities), fair value	$ 2,046	$ 710

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