Fair Value - Estimated fair value and related carrying amount, of the Company's financial instruments (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Financial assets:
Trading securities	$ 31,263	$ 77,689
SBA servicing asset	6,100
Financial liabilities:
Other borrowings	392,275
Other derivative financial instruments (mortgage banking related)	741,583	(516,271)	$ (113,788)
Carrying Amount
Financial assets:
Cash and cash equivalents	1,312,563	6,721,571
Trading securities	31,263	77,689
Investment securities	8,189,780	7,173,947
Loans held for sale	28,968	191,723
Loans, net of allowance for credit losses	29,821,418	23,626,359
Accrued interest receivable	134,594	90,069
Mortgage servicing rights	86,610	65,620
SBA servicing asset	6,068
Interest rate swap - non-designated hedge	210,216	408,776
Other derivative financial instruments (mortgage banking related)	$ 800	$ 5,966
Derivative Asset, Statement of Financial Position [Extensible Enumeration]	Derivative Asset, Noncurrent	Derivative Asset, Noncurrent
Financial liabilities:
Deposits	$ 36,350,623	$ 35,054,829
Federal funds purchased and securities sold under agreements to repurchase	556,417	781,239
Other borrowings	392,275	327,066
Accrued interest payable	6,218	3,345
Interest rate swap - non-designated hedge	1,033,980	288,561
Other derivative financial instruments (mortgage banking related)	163
Fair Value
Financial assets:
Cash and cash equivalents	1,312,563	6,721,571
Trading securities	31,263	77,689
Investment securities	7,756,707	7,132,110
Loans held for sale	28,968	191,723
Loans, net of allowance for credit losses	29,329,499	23,921,372
Accrued interest receivable	134,594	90,069
Mortgage servicing rights	86,610	65,620
Interest rate swap - non-designated hedge	210,216	408,776
Other derivative financial instruments (mortgage banking related)	$ 800	$ 5,966
Derivative Asset, Statement of Financial Position [Extensible Enumeration]	Derivative Asset, Noncurrent	Derivative Asset, Noncurrent
Financial liabilities:
Deposits	$ 36,264,401	$ 35,050,516
Federal funds purchased and securities sold under agreements to repurchase	556,417	781,239
Other borrowings	377,360	334,640
Accrued interest payable	6,218	3,345
Interest rate swap - non-designated hedge	1,033,980	288,561
Other derivative financial instruments (mortgage banking related)	163
Commitments to extend credit \| Fair Value
Financial liabilities:
Commitments to extend credit	(184,801)	93,501
Quoted Prices In Active Markets for Identical Assets (Level 1)
Financial assets:
Cash and cash equivalents	1,312,563	6,721,571
Investment securities	179,717	160,568
Significant Other Observable Inputs (Level 2)
Financial assets:
Trading securities	31,263	77,689
Investment securities	7,576,990	6,971,542
Loans held for sale	28,968	191,723
Accrued interest receivable	28,449	19,241
Interest rate swap - non-designated hedge	210,216	408,776
Other derivative financial instruments (mortgage banking related)	$ 800	$ 5,966
Derivative Asset, Statement of Financial Position [Extensible Enumeration]	Derivative Asset, Noncurrent	Derivative Asset, Noncurrent
Financial liabilities:
Deposits	$ 36,264,401	$ 35,050,516
Federal funds purchased and securities sold under agreements to repurchase	556,417	781,239
Other borrowings	377,360	334,640
Accrued interest payable	6,218	3,345
Interest rate swap - non-designated hedge	1,033,980	288,561
Other derivative financial instruments (mortgage banking related)	163
Significant Other Observable Inputs (Level 2) \| Commitments to extend credit
Financial liabilities:
Commitments to extend credit	(184,801)	93,501
Significant Unobservable Inputs (Level 3)
Financial assets:
Loans, net of allowance for credit losses	29,329,499	23,921,372
Accrued interest receivable	106,145	70,828
Mortgage servicing rights	86,610	$ 65,620
SBA servicing asset	$ 6,068

Fair value of accrued interest payable as on date.

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- Definition

Fair value of accrued interest receivable as on date.

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No definition available.

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Fair value portion of arrangements to extend credit.

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No definition available.

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The 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, the 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. The item represents residential mortgage servicing rights as presented on the statement of financial position which are due to the entity as of the balance sheet date.

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Fair value portion of Small Business administration servicing assets.

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- Definition

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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- Definition

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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No definition available.

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Indicates line item in statement of financial position that includes derivative asset.

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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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- Definition

Amount after offset of short term borrowing where a bank borrows, at the federal funds rate, from another bank and securities that an entity sells and agrees to repurchase at a specified date for a specified price.

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The increase (decrease) during the period in the carrying value of derivative instruments reported as liabilities that are due to be disposed of within one year (or the normal operating cycle, if longer).

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Fair value as of the balance sheet date of all derivative assets not designated as hedging instruments.

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Fair value as of the balance sheet date of all derivative liabilities not designated as hedging instruments.

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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- Definition

The fair value amount of long-term debt 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.

+ References

No definition available.

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The carrying amount as of the balance sheet date for the aggregate of other miscellaneous borrowings owed by the reporting entity.

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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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