Fair Value Measurements (Financial Assets and Liabilities Measured at Fair Value on Recurring Basis) (Details) - USD ($) $ in Thousands		Sep. 30, 2024	Dec. 31, 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets		$ 55,440	$ 84,458
Derivative liabilities		52,690	87,567
Total recurring fair value measurements - liabilities		2,300	1,300
Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale debt securities		5,296,147	4,915,195
Mortgage loans held for sale		23,462	13,269
Derivative assets	[1]	69,815	90,712
Total fair value measurements		5,389,424	5,019,176
Derivative liabilities	[1]	132,029	207,138
Total recurring fair value measurements - liabilities		132,029	207,138
Recurring [Member] | U.S. Treasury And Government Agency Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale debt securities		173,768	97,808
Recurring [Member] | Municipal Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale debt securities		199,359	201,412
Recurring [Member] | Corporate Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale debt securities		21,454	20,352
Recurring [Member] | Residential Mortgage-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale debt securities		2,195,672	2,113,866
Recurring [Member] | Commercial Mortgage-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale debt securities		2,667,908	2,437,472
Recurring [Member] | Collateralized Mortgage Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale debt securities		37,986	44,285
Recurring [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale debt securities		5,296,147	4,915,195
Mortgage loans held for sale		23,462	13,269
Derivative assets	[1]	69,815	90,712
Total fair value measurements		5,389,424	5,019,176
Derivative liabilities	[1]	129,768	205,796
Total recurring fair value measurements - liabilities		129,768	205,796
Recurring [Member] | Level 2 [Member] | U.S. Treasury And Government Agency Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale debt securities		173,768	97,808
Recurring [Member] | Level 2 [Member] | Municipal Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale debt securities		199,359	201,412
Recurring [Member] | Level 2 [Member] | Corporate Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale debt securities		21,454	20,352
Recurring [Member] | Level 2 [Member] | Residential Mortgage-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale debt securities		2,195,672	2,113,866
Recurring [Member] | Level 2 [Member] | Commercial Mortgage-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale debt securities		2,667,908	2,437,472
Recurring [Member] | Level 2 [Member] | Collateralized Mortgage Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale debt securities		37,986	44,285
Recurring [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	[1]	2,261	1,342
Total recurring fair value measurements - liabilities		$ 2,261	$ 1,342

[1] For further disaggregation of derivative assets and liabilities, see Note 6 - Derivatives.