Derivatives (Fair Values of Derivative Financial Instruments) (Details) - USD ($)		6 Months Ended	12 Months Ended
		Jun. 30, 2025	Dec. 31, 2024
Derivatives Fair Value [Line Items]
Notional or Contractual Amount		$ 7,474,521,000	$ 7,392,532,000
Fair Values, Assets		55,113,000	71,893,000
Fair Values, Assets	[1]	121,090,000	150,253,000
Less: netting adjustment	[1]	(50,007,000)	(76,413,000)	[2]
Total derivative assets/liabilities	[1]	71,083,000	73,840,000
Fair Values, Liabilities		45,328,000	54,707,000
Fair Values, Liabilities	[1]	118,519,000	160,623,000
Less: netting adjustment	[1]	(2,000)
Other Liabilities [Member]
Derivatives Fair Value [Line Items]
Total derivative assets/liabilities	[1]	118,517,000	160,623,000
Derivatives Designated as Hedging Instruments [Member]
Derivatives Fair Value [Line Items]
Notional or Contractual Amount		2,102,500,000	1,827,500,000
Fair Values, Assets	[1]	30,571,000	39,647,000
Fair Values, Liabilities	[1]	26,809,000	48,022,000
Derivatives Not Designated as Hedging Instruments [Member]
Derivatives Fair Value [Line Items]
Notional or Contractual Amount		5,372,021,000	5,565,032,000
Fair Values, Assets	[1]	90,519,000	110,606,000
Fair Values, Liabilities	[1]	91,710,000	112,601,000
Derivatives Not Designated as Hedging Instruments [Member] | Interest Rate Swaps [Member]
Derivatives Fair Value [Line Items]
Notional or Contractual Amount		4,732,198,000	4,926,461,000
Fair Values, Assets	[1]	82,944,000	108,702,000
Fair Values, Liabilities	[1]	83,132,000	108,761,000
Derivatives Not Designated as Hedging Instruments [Member] | Risk Participation Agreements [Member]
Derivatives Fair Value [Line Items]
Notional or Contractual Amount		379,301,000	445,554,000
Fair Values, Assets	[1]	14,000	7,000
Fair Values, Liabilities	[1]	12,000	9,000
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		40,167,000	25,526,000
Fair Values, Assets	[1]	1,026,000
Fair Values, Liabilities	[1]		383,000
Derivatives Not Designated as Hedging Instruments [Member] | Forward Commitments to Sell Residential Mortgage Loans [Member]
Derivatives Fair Value [Line Items]
Notional or Contractual Amount		14,957,000	27,465,000
Fair Values, Assets	[1]		420,000
Fair Values, Liabilities	[1]	269,000	0
Derivatives Not Designated as Hedging Instruments [Member] | To Be Announced (TBA) Securities [Member]
Derivatives Fair Value [Line Items]
Notional or Contractual Amount		34,500,000	15,250,000
Fair Values, Assets	[1]	2,000	88,000
Fair Values, Liabilities	[1]	196,000	1,000
Derivatives Not Designated as Hedging Instruments [Member] | Foreign Exchange Forward Contracts [Member]
Derivatives Fair Value [Line Items]
Notional or Contractual Amount		128,996,000	82,756,000
Fair Values, Assets	[1]	6,533,000	1,389,000
Fair Values, Liabilities	[1]	6,480,000	1,358,000
Derivatives Not Designated as Hedging Instruments [Member] | Visa Class B derivative contract [Member]
Derivatives Fair Value [Line Items]
Notional or Contractual Amount		41,902,000	42,020,000
Fair Values, Liabilities	[1]	1,621,000	2,089,000
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		1,625,000,000	1,350,000,000
Fair Values, Assets	[1]	4,041,000
Fair Values, Liabilities	[1]	26,809,000	48,022,000
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]	$ 26,530,000	$ 39,647,000

[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.