Fair Value - Carrying Amounts and Estimated Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity	$ 1,426,279	$ 1,494,514
Deposits	15,569,763	14,437,648
Federal funds purchased and securities sold under repurchase agreements	405,745	449,331
Other borrowings	483,230	1,050,938
Subordinated notes	123,482	123,262
Junior subordinated debt securities	61,856	61,856
Level 2 [Member] | Carrying Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and short-term investments	975,543	738,787
Securities held to maturity	1,426,279	1,494,514
Deposits	15,569,763	14,437,648
Federal funds purchased and securities sold under repurchase agreements	405,745	449,331
Other borrowings	483,230	1,050,938
Subordinated notes	123,482	123,262
Junior subordinated debt securities	61,856	61,856
Level 2 [Member] | Estimate Fair Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and short-term investments	975,543	738,787
Securities held to maturity	1,355,504	1,406,589
Deposits	15,553,417	14,404,661
Federal funds purchased and securities sold under repurchase agreements	405,745	449,331
Other borrowings	483,226	1,050,932
Subordinated notes	108,125	113,125
Junior subordinated debt securities	46,856	46,392
Level 3 [Member] | Carrying Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net LHFI	12,811,157	12,083,825
Level 3 [Member] | Estimate Fair Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net LHFI	$ 12,762,505	$ 11,850,318