Derivatives and Hedging Activities (FV of Derivative Financial Instruments and Classification on Balance Sheet) (Details) - USD ($) $ in Thousands		Sep. 30, 2021	Dec. 31, 2020
Derivatives, Fair Value [Line Items]
Derivative Asset	[1]	$ 111,550	$ 187,422
Derivative Liability	[2]	76,696	117,959
Derivative Asset, Fair Value, Amount Offset Against Collateral	[1]	74,636	138,636
Derivative, Collateral, Obligation to Return Securities	[3]	36,914	48,786
Derivative, Collateral, Right to Reclaim Securities	[3]	36,914	48,786
Derivative, Collateral, Obligation to Return Cash		0	0
Derivative, Collateral, Right to Reclaim Cash		33,249	62,460
Derivative Liability, Fair Value, Amount Offset Against Collateral	[2]	6,533	6,713
Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Asset, at Fair Value	[1]	83,978	138,613
Derivative Asset, Fair Value, Gross Asset	[1]	116,358	187,399
Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Liability, at Fair Value	[2]	82,164	132,722
Liability Derivatives	[2]	83,150	134,064
Interest rate swaps [Member] | Derivatives designated as hedges [Member] | Other Assets [Member]
Derivatives, Fair Value [Line Items]
Interest Rate Derivative Assets, at Fair Value	[1],[4]	32,380	48,786
Interest rate swaps [Member] | Derivatives designated as hedges [Member] | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Interest Rate Derivative Liabilities, at Fair Value	[2],[5]	986	1,342
Loan level swaps [Member] | Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	[1],[4]	76,552	127,228
Loan level swaps [Member] | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives	[2],[5]	76,548	127,218
Foreign exchange contracts | Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	[1]	5,531	4,359
Foreign exchange contracts | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives	[2]	5,530	4,349
Risk Participation Agreement | Other Assets [Member]
Derivatives, Fair Value [Line Items]
Credit Risk Derivative Assets, at Fair Value	[1]	236	513
Risk Participation Agreement | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Credit Risk Derivative Liabilities, at Fair Value	[2]	64	119
Interest Rate Lock Commitments [Member] | Not Designated as Hedging Instrument | Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Instrument Not Designated as a Hedge, Interest Rate Lock Commitments, Asset at Fair Value	[1]	1,202	6,513
Derivative Instrument Not Designated as a Hedge, Forward Sales Agreements, Asset at Fair Value	[1]	0	0
Derivative Instrument Not Designated as a Hedge, Forward Sale Hedge Commitment, Asset at Fair Value	[1]	457	0
Interest Rate Lock Commitments [Member] | Not Designated as Hedging Instrument | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Instrument Not Designated as a Hedge, Interest Rate Lock Commitments, Liabilities at Fair Value	[2]	0	0
Derivative Instrument Not Designated as a Hedge, Forward Sales Agreements, Liabilities at Fair Value	[2]	22	1
Derivative Instrument Not Designated as a Hedge, Forward Sale Hedge Commitment, Liability at Fair Value	[2]	0	1,035
CME [Member]
Derivatives, Fair Value [Line Items]
Derivative, Collateral, Obligation to Return Cash	[6]	4,808	(23)
Derivative, Collateral, Right to Reclaim Cash	[6]	$ 6,454	$ 16,105

[1] All asset derivatives are located in other assets on the balance sheet.

[2] All liability derivatives are located in other liabilities on the balance sheet.

[3] Reflects offsetting derivative positions with the same counterparty that are not netted on the balance sheet.

[4] Approximately $1.2 million and $1.6 million of accrued interest receivable is included in the fair value of the interest rate and loan level asset derivatives, respectively, as of September 30, 2021. Accrued interest receivable of approximately $1.2 million and $2.0 million is included in the fair value of the interest rate and loan level asset derivatives, respectively, as of December 31, 2020.

[5] Approximately $60,000 and $1.6 million of accrued interest payable is included in the fair value of the interest rate and loan level liability derivatives, respectively, as of September 30, 2021. Accrued interest payable of approximately $81,000 and $2.0 million is included in the fair value of the interest rate and loan level derivative liabilities, respectively, as of December 31, 2020.

[6] Netting adjustments represent the amounts recorded to convert derivative assets and liabilities cleared through CME from a gross basis to a net basis, inclusive of the variation margin payments, in accordance with applicable accounting guidance. As displayed in the table above, derivatives that cleared through the CME were either in a net asset position or a net liability position as of September 30, 2021.