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, 2022	Dec. 31, 2021
Financial assets
Securities held to maturity	$ 424,685	$ 415,552
Securities available for sale	2,528,253	2,386,052
Loans held for sale	196,598	453,533
Loans, net	10,437,613	9,856,743
Mortgage servicing rights	94,743	89,018
Derivative instruments	27,413	8,007
Financial liabilities
Derivative instruments	17,561	13,436
Carrying Value
Financial assets
Cash and cash equivalents	1,010,468	1,877,965
Securities held to maturity	488,851	416,357
Securities available for sale	2,528,253	2,386,052
Loans held for sale	196,598	453,533
Loans, net	10,437,613	9,856,743
Mortgage servicing rights	94,743	89,018
Derivative instruments	31,372	17,698
Financial liabilities
Deposits	13,763,929	13,905,724
Short-term borrowings	112,642	13,947
Federal Home Loan Bank advances		417
Junior subordinated debentures	111,662	111,373
Subordinated notes	319,891	359,419
Derivative instruments	23,497	13,803
Fair Value
Financial assets
Cash and cash equivalents	1,010,468	1,877,965
Securities held to maturity	424,685	415,552
Securities available for sale	2,528,253	2,386,052
Loans held for sale	196,598	453,533
Loans, net	10,140,151	9,690,604
Mortgage servicing rights	137,879	99,425
Derivative instruments	31,372	17,698
Financial liabilities
Deposits	13,734,851	13,902,739
Short-term borrowings	112,642	13,947
Federal Home Loan Bank advances		422
Junior subordinated debentures	102,093	106,682
Subordinated notes	307,350	373,950
Derivative instruments	23,497	13,803
Fair Value \| Level 1
Financial assets
Cash and cash equivalents	1,010,468	1,877,965
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	12,488,130	12,494,342
Short-term borrowings	112,642	13,947
Federal Home Loan Bank advances		0
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	424,685	415,552
Securities available for sale	2,528,253	2,386,052
Loans held for sale	196,598	453,533
Loans, net	0	0
Mortgage servicing rights	0	0
Derivative instruments	31,372	17,698
Financial liabilities
Deposits	1,246,721	1,408,397
Short-term borrowings	0	0
Federal Home Loan Bank advances		422
Junior subordinated debentures	102,093	106,682
Subordinated notes	307,350	373,950
Derivative instruments	23,497	13,803
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	10,140,151	9,690,604
Mortgage servicing rights	137,879	99,425
Derivative instruments	0	0
Financial liabilities
Deposits	0	0
Short-term borrowings	0	0
Federal Home Loan Bank advances		0
Junior subordinated debentures	0	0
Subordinated notes	0	0
Derivative instruments	$ 0	$ 0

Junior Subordinated Debt Obligations, Fair Value Disclosure

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Fair value of subordinated debt obligations including, but not limited to, subordinated loan, subordinated bond, subordinated debenture or junior debt.

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Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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Amount, after valuation allowance, of financing receivable held for sale and not part of disposal group. Excludes loan covered under loss sharing agreement and loan classified as investment in debt security.

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Amortized cost, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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Amortized amount of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents the amount of short-term debt existing as of the balance sheet date.

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