Derivatives (Effects of Derivative Instruments in the Statements of Income) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Derivative Instruments, Gain (Loss) [Line Items]
Derivative income reflected in income statement	$ (7,440)	$ 4,292	$ (17,502)	$ 27,745
Derivatives Designated as Hedging Instruments [Member] | Cash Flow Hedge [Member] | Interest Rate Swaps - Variable Rate Loans [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative income reflected in income statement	$ (11,116)	$ 1,752	$ (28,609)	$ 14,519
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Interest and Fee Income, Loan and Lease, Held-in-Portfolio	Interest and Fee Income, Loan and Lease, Held-in-Portfolio	Interest and Fee Income, Loan and Lease, Held-in-Portfolio	Interest and Fee Income, Loan and Lease, Held-in-Portfolio
Derivatives Designated as Hedging Instruments [Member] | Fair Value Hedging [Member] | Interest Rate Swaps - Securities [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative income reflected in income statement	$ 3,023	$ 1,596	$ 8,786	$ 2,625
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Interest Income, Securities, Operating, Taxable	Interest Income, Securities, Operating, Taxable	Interest Income, Securities, Operating, Taxable	Interest Income, Securities, Operating, Taxable
Derivatives Designated as Hedging Instruments [Member] | Fair Value Hedging [Member] | Securities Termination [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative income reflected in income statement	$ 0	$ 0	$ 0	$ 1,620
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Debt and Equity Securities, Gain (Loss)	Debt and Equity Securities, Gain (Loss)	Debt and Equity Securities, Gain (Loss)	Debt and Equity Securities, Gain (Loss)
Derivatives Not Designated as Hedging Instruments [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative income reflected in income statement	$ 418	$ 1,309	$ 1,585	$ 6,386
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Noninterest Income, Other	Noninterest Income, Other	Noninterest Income, Other	Noninterest Income, Other
Derivatives Not Designated as Hedging Instruments [Member] | Residential mortgage banking
Derivative Instruments, Gain (Loss) [Line Items]
Derivative income reflected in income statement	$ 235	$ (365)	$ 736	$ 2,595
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Noninterest Income	Noninterest Income	Noninterest Income	Noninterest Income