Investment Securities Schedule of Amortized Cost and Fair Values of Investment Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Schedule of Investments [Line Items]
Amortized Cost	$ 3,259,122
Gross Unrealized Gains	2,107
Gross Unrealized Losses	(321,635)
Estimated Fair Value	2,939,594	$ 2,398,352
Amortized Cost, Held to Maturity	1,244,433	1,267,922
Gross Unrealized Gains, Held to Maturity	0	0
Gross Unrealized Losses, Held to Maturity	(210,994)	(195,715)
Debt Securities, Held-to-Maturity, Fair Value	1,033,439	1,072,207
US Government Debt Securities
Schedule of Investments [Line Items]
Amortized Cost		42,475
Gross Unrealized Gains		0
Gross Unrealized Losses		(314)
Estimated Fair Value		42,161
US Government Agencies Debt Securities
Schedule of Investments [Line Items]
Amortized Cost		1,038
Gross Unrealized Gains		0
Gross Unrealized Losses		(28)
Estimated Fair Value		1,010
US States and Political Subdivisions Debt Securities [Member]
Schedule of Investments [Line Items]
Amortized Cost	965,392	1,200,571
Gross Unrealized Gains	50	1,089
Gross Unrealized Losses	(145,333)	(129,647)
Estimated Fair Value	820,109	1,072,013
Corporate Debt Securities [Member]
Schedule of Investments [Line Items]
Amortized Cost	368,901	480,714
Gross Unrealized Gains	510	473
Gross Unrealized Losses	(32,013)	(40,636)
Estimated Fair Value	337,398	440,551
Collateralized Mortgage Obligations [Member]
Schedule of Investments [Line Items]
Amortized Cost	724,602	122,824
Gross Unrealized Gains	1,533	0
Gross Unrealized Losses	(12,366)	(11,390)
Estimated Fair Value	713,769	111,434
Mortgage-Backed Securities [Member]
Schedule of Investments [Line Items]
Amortized Cost	589,267	223,273
Gross Unrealized Gains	14	7
Gross Unrealized Losses	(32,090)	(26,485)
Estimated Fair Value	557,191	196,795
Amortized Cost, Held to Maturity	384,956	407,075
Gross Unrealized Gains, Held to Maturity	0	0
Gross Unrealized Losses, Held to Maturity	(58,593)	(51,805)
Debt Securities, Held-to-Maturity, Fair Value	326,363	355,270
Commercial Mortgage Backed Securities [Member]
Schedule of Investments [Line Items]
Amortized Cost	610,960	627,364
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(99,833)	(92,976)
Estimated Fair Value	511,127	534,388
Amortized Cost, Held to Maturity	859,477	860,847
Gross Unrealized Gains, Held to Maturity	0	0
Gross Unrealized Losses, Held to Maturity	(152,401)	(143,910)
Debt Securities, Held-to-Maturity, Fair Value	$ 707,076	716,937
Debt Securities [Member]
Schedule of Investments [Line Items]
Amortized Cost		2,698,259
Gross Unrealized Gains		1,569
Gross Unrealized Losses		(301,476)
Estimated Fair Value		$ 2,398,352