Derivative and Hedging Activities, Derivative Instruments Not Designated as Hedging Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Forward commitment fair value	$ 108
Asset
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Derivatives (trading and other assets), fair value	264,445	$ 104,305
Less: Legally enforceable master netting agreements	2,524	10,410
Less: Cash collateral pledged/received	24,837	1,408
Derivative Asset	237,084	92,487
Liability
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Derivatives (trading and other liabilities), fair value	57,999	37,455
Less: Legally enforceable master netting agreements	2,524	10,410
Less: Cash collateral pledged/received	28,363	11,365
Derivatives (trading liabilities)	27,112	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	3,731,752	3,029,877
Derivatives (trading and other assets), fair value	225,912	77,024
Not designated as hedging instruments \| Asset \| Foreign currency exchange forwards
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	431,862	272,636
Derivatives (trading and other assets), fair value	4,710	4,226
Not designated as hedging instruments \| Asset \| Commodity contracts
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	132,055	255,089
Derivatives (trading and other assets), fair value	25,935	20,528
Not designated as hedging instruments \| Asset \| Mortgage banking(a)(b)
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	171,871	255,291
Derivatives (trading and other assets), fair value	7,888	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	3,731,752	3,029,877
Derivatives (trading and other liabilities), fair value	28,960	13,073
Not designated as hedging instruments \| Liability \| Foreign currency exchange forwards
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	422,645	264,653
Derivatives (trading and other liabilities), fair value	4,563	4,048
Not designated as hedging instruments \| Liability \| Commodity contracts
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	127,597	255,165
Derivatives (trading and other liabilities), fair value	24,476	19,624
Not designated as hedging instruments \| Liability \| Mortgage banking(a)(b)
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	264,000	263,000
Derivatives (trading and other liabilities), fair value	$ 0	$ 710

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