Fair Value Measurements - Assets and Liabilities Not Measured and Reported at Fair Value on a Recurring Basis or Nonrecurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Financial assets
Securities held to maturity	$ 1,068,968	$ 1,121,830
Securities available for sale	764,844	923,279
Loans held for sale	291,735	179,756
Mortgage servicing rights	71,990	91,688
Derivative instruments	24,514	29,284
Financial liabilities
Derivative instruments	20,661	26,425
Carrying Value
Financial assets
Cash and cash equivalents	1,275,620	801,351
Securities held to maturity	1,150,531	1,221,464
Securities available for sale	764,844	923,279
Loans held for sale	291,735	179,756
Loans, net	12,427,270	12,152,652
Mortgage servicing rights	71,990	91,688
Derivative instruments	39,963	37,151
Financial liabilities
Deposits	14,509,751	14,076,785
Short-term borrowings	108,732	307,577
Junior subordinated debentures	113,681	112,978
Subordinated notes	319,496	316,422
Derivative instruments	34,555	33,608
Fair Value
Financial assets
Cash and cash equivalents	1,275,620	801,351
Securities held to maturity	1,068,968	1,121,830
Securities available for sale	764,844	923,279
Loans held for sale	291,735	179,756
Loans, net	12,051,978	11,594,363
Mortgage servicing rights	88,461	117,664
Derivative instruments	39,963	37,151
Financial liabilities
Deposits	14,504,221	14,060,050
Short-term borrowings	108,732	307,577
Junior subordinated debentures	98,822	96,435
Subordinated notes	286,140	255,192
Derivative instruments	34,555	33,608
Fair Value | Level 1
Financial assets
Cash and cash equivalents	1,275,620	801,351
Securities held to maturity	0	0
Securities available for sale	0	0
Loans held for sale	0	0
Loans, net	0	0
Mortgage servicing rights	0	0
Derivative instruments	0	0
Financial liabilities
Deposits	11,816,487	11,381,556
Short-term borrowings	108,732	307,577
Junior subordinated debentures	0	0
Subordinated notes	0	0
Derivative instruments	0	0
Fair Value | Level 2
Financial assets
Cash and cash equivalents	0	0
Securities held to maturity	1,068,968	1,121,830
Securities available for sale	764,844	923,279
Loans held for sale	291,735	179,756
Loans, net	0	0
Mortgage servicing rights	0	0
Derivative instruments	39,963	37,151
Financial liabilities
Deposits	2,687,734	2,678,494
Short-term borrowings	0	0
Junior subordinated debentures	98,822	96,435
Subordinated notes	286,140	255,192
Derivative instruments	34,555	33,608
Fair Value | Level 3
Financial assets
Cash and cash equivalents	0	0
Securities held to maturity	0	0
Securities available for sale	0	0
Loans held for sale	0	0
Loans, net	12,051,978	11,594,363
Mortgage servicing rights	88,461	117,664
Derivative instruments	0	0
Financial liabilities
Deposits	0	0
Short-term borrowings	0	0
Junior subordinated debentures	0	0
Subordinated notes	0	0
Derivative instruments	$ 0	$ 0