Derivative and Hedging Activities, Derivative Instruments Not Designated as Hedging Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Fair Value, Inputs, Level 3
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Derivative Asset	$ 4,255	$ 0
Derivatives (trading liabilities)	0	2,046
Fair Value, Inputs, Level 3 \| Forward commitments (mortgage)
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Derivative Asset	4,255	0
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	121,020	192,518
Derivatives (trading liabilities)	28,382	25,680
Fair Value, Inputs, Level 2 \| Commodity contracts \| Fair Value, Measurements, Recurring
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Derivative Asset	5,808	12,486
Derivatives (trading liabilities)	5,098	11,155
Asset
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Derivatives (trading and other assets), fair value	141,043	219,537
Less: Legally enforceable master netting agreements	2,643	1,936
Less: Cash collateral pledged/received	1,581	10,879
Derivative Asset	136,819	206,722
Liability
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Derivatives (trading and other liabilities), fair value	36,308	43,716
Less: Legally enforceable master netting agreements	2,643	1,936
Less: Cash collateral pledged/received	17,583	25,625
Derivatives (trading liabilities)	16,082	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	3,654,732	3,639,679
Not designated as hedging instruments \| Asset \| Foreign currency exchange forwards
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	448,395	411,292
Not designated as hedging instruments \| Asset \| Commodity contracts
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	70,633	87,547
Not designated as hedging instruments \| Asset \| Mortgage banking(a)(b)
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	292,704	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	3,654,732	3,639,679
Not designated as hedging instruments \| Liability \| Foreign currency exchange forwards
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	439,381	398,890
Not designated as hedging instruments \| Liability \| Commodity contracts
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	70,758	83,214
Not designated as hedging instruments \| Liability \| Mortgage banking(a)(b)
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	$ 408,500	$ 335,500

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

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