Derivatives (Fair Values of Derivative Financial Instruments) (Details) - USD ($)		6 Months Ended	12 Months Ended
		Jun. 30, 2024	Dec. 31, 2023
Derivatives Fair Value [Line Items]
Notional or contractual amount		$ 7,654,954,000	$ 7,691,719,000
Fair Values, Assets		$ 91,647,000	$ 84,458,000
Derivative Asset, Statement of Financial Position [Extensible Enumeration]		Other Assets	Other Assets
Fair Values, Assets	[1]	$ 171,340,000	$ 156,360,000
Less: netting adjustment	[1]	(80,340,000)	(65,648,000)	[2]
Total derivative assets/liabilities	[1]	91,000,000	90,712,000
Fair Values, Liabilities		93,407,000	87,567,000
Fair Values, Liabilities	[1]	226,442,000	207,138,000
Other Liabilities [Member]
Derivatives Fair Value [Line Items]
Total derivative assets/liabilities	[1]	226,442,000	207,138,000
Derivatives Designated as Hedging Instruments [Member]
Derivatives Fair Value [Line Items]
Notional or contractual amount		2,027,500,000	2,027,500,000
Fair Values, Assets	[1]	34,289,000	22,819,000
Fair Values, Liabilities	[1]	87,027,000	73,611,000
Derivatives Not Designated as Hedging Instruments [Member]
Derivatives Fair Value [Line Items]
Notional or contractual amount		5,627,454,000	5,664,219,000
Fair Values, Assets	[1]	137,051,000	133,541,000
Fair Values, Liabilities	[1]	139,415,000	133,527,000
Derivatives Not Designated as Hedging Instruments [Member] | Interest Rate Swaps [Member]
Derivatives Fair Value [Line Items]
Notional or contractual amount		4,995,388,000	5,128,144,000
Fair Values, Assets	[1]	135,554,000	131,271,000
Fair Values, Liabilities	[1]	135,687,000	129,994,000
Derivatives Not Designated as Hedging Instruments [Member] | Risk Participation Agreements [Member]
Derivatives Fair Value [Line Items]
Notional or contractual amount		357,704,000	364,906,000
Fair Values, Assets	[1]	10,000	34,000
Fair Values, Liabilities	[1]	4,000	18,000
Derivatives Not Designated as Hedging Instruments [Member] | Interest Rate-Lock Commitments on Residential Mortgage Loans [Member]
Derivatives Fair Value [Line Items]
Notional or contractual amount		43,937,000	13,355,000
Fair Values, Assets	[1]	736,000
Fair Values, Liabilities	[1]		286,000
Derivatives Not Designated as Hedging Instruments [Member] | Forward Commitments to Sell Residential Mortgage Loans [Member]
Derivatives Fair Value [Line Items]
Notional or contractual amount		30,600,000	18,563,000
Fair Values, Assets	[1]		372,000
Fair Values, Liabilities	[1]	570,000	0
Derivatives Not Designated as Hedging Instruments [Member] | To Be Announced (TBA) Securities [Member]
Derivatives Fair Value [Line Items]
Notional or contractual amount		28,000,000	13,500,000
Fair Values, Assets	[1]	110,000
Fair Values, Liabilities	[1]	9,000	47,000
Derivatives Not Designated as Hedging Instruments [Member] | Foreign Exchange Forward Contracts [Member]
Derivatives Fair Value [Line Items]
Notional or contractual amount		129,208,000	83,134,000
Fair Values, Assets	[1]	641,000	1,864,000
Fair Values, Liabilities	[1]	592,000	1,840,000
Derivatives Not Designated as Hedging Instruments [Member] | Visa Class B derivative contract [Member]
Derivatives Fair Value [Line Items]
Notional or contractual amount		42,617,000	42,617,000
Fair Values, Liabilities	[1]	2,553,000	1,342,000
Cash Flow Hedge [Member] | Derivatives Designated as Hedging Instruments [Member] | Interest Rate Swaps - Variable Rate Loans [Member]
Derivatives Fair Value [Line Items]
Notional or contractual amount		1,550,000,000	1,550,000,000
Fair Values, Liabilities	[1]	$ 87,027,000	$ 73,611,000
Fair Value Hedging [Member] | Derivatives Designated as Hedging Instruments [Member] | Interest Rate Swaps - Variable Rate Loans [Member]
Derivatives Fair Value [Line Items]
Derivative Asset, Statement of Financial Position [Extensible Enumeration]		Other Assets	Other Assets
Derivative Liability, Statement of Financial Position [Extensible Enumeration]		Other Liabilities	Other Liabilities
Fair Value Hedging [Member] | Derivatives Designated as Hedging Instruments [Member] | Interest Rate Swaps - Securities [Member]
Derivatives Fair Value [Line Items]
Notional or contractual amount		$ 477,500,000	$ 477,500,000
Fair Values, Assets	[1]	$ 34,289,000	$ 22,819,000
Derivative Asset, Statement of Financial Position [Extensible Enumeration]		Other Assets	Other Assets
Derivative Liability, Statement of Financial Position [Extensible Enumeration]		Other Liabilities	Other Liabilities

[1] Derivative assets and liabilities are reported in other assets and other liabilities, respectively, in the consolidated balance sheets.

[2] Represents balance sheet netting of derivative assets and liabilities for variation margin collateral held or placed with the same central clearing counterparty. See offsetting assets and liabilities for further information.