Fair Value Measurements - Assets and Liabilities Not Measured and Reported at Fair Value on a Recurring Basis or Nonrecurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Financial assets
Securities held to maturity	$ 1,052,705	$ 1,121,830
Securities available for sale	749,685	923,279
Loans held for sale	266,406	179,756
Mortgage servicing rights	72,092	91,688
Derivative instruments	35,654	29,284
Financial liabilities
Derivative instruments	33,598	26,425
Carrying Value
Financial assets
Cash and cash equivalents	851,906	801,351
Securities held to maturity	1,174,663	1,221,464
Securities available for sale	749,685	923,279
Loans held for sale	266,406	179,756
Loans, net	12,404,884	12,152,652
Mortgage servicing rights	72,092	91,688
Derivative instruments	39,938	37,151
Financial liabilities
Deposits	14,255,213	14,076,785
Short-term borrowings	232,741	307,577
Junior subordinated debentures	113,447	112,978
Subordinated notes	315,230	316,422
Derivative instruments	36,050	33,608
Fair Value
Financial assets
Cash and cash equivalents	851,906	801,351
Securities held to maturity	1,052,705	1,121,830
Securities available for sale	749,685	923,279
Loans held for sale	266,406	179,756
Loans, net	11,932,069	11,594,363
Mortgage servicing rights	97,781	117,664
Derivative instruments	39,938	37,151
Financial liabilities
Deposits	14,239,166	14,060,050
Short-term borrowings	232,741	307,577
Junior subordinated debentures	97,655	96,435
Subordinated notes	271,793	255,192
Derivative instruments	36,050	33,608
Fair Value | Level 1
Financial assets
Cash and cash equivalents	851,906	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	11,556,358	11,381,556
Short-term borrowings	232,741	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	1,052,705	1,121,830
Securities available for sale	749,685	923,279
Loans held for sale	266,406	179,756
Loans, net	0	0
Mortgage servicing rights	0	0
Derivative instruments	39,938	37,151
Financial liabilities
Deposits	2,682,808	2,678,494
Short-term borrowings	0	0
Junior subordinated debentures	97,655	96,435
Subordinated notes	271,793	255,192
Derivative instruments	36,050	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	11,932,069	11,594,363
Mortgage servicing rights	97,781	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