Fair Value (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Financial assets:
Trading securities	$ 77,689	$ 10,674
Financial liabilities:
Other borrowings	327,066
Other derivative financial instruments (mortgage banking related)	(394,695)	(113,788)	$ 26,064
Carrying Amount
Financial assets:
Cash and cash equivalents	6,843,147	4,609,255
Trading securities	77,689	10,674
Investment securities	7,173,947	4,446,657
Loans held for sale	191,723	290,467
Loans, net of allowance for credit losses	23,626,359	24,206,825
Accrued interest receivable	90,069	107,601
Mortgage servicing rights	65,620	43,820
Interest rate swap - non-designated hedge	408,776	802,763
Other derivative financial instruments (mortgage banking related)	5,966	11,136
Financial liabilities:
Deposits	35,054,829	30,693,882
Federal funds purchased and securities sold under agreements to repurchase	781,239	779,666
Other borrowings	327,066	390,179
Accrued interest payable	3,345	7,103
Interest rate swap - non-designated hedge	410,137	804,832
Fair Value
Financial assets:
Cash and cash equivalents	6,843,147	4,609,255
Trading securities	77,689	10,674
Investment securities	7,132,110	4,448,300
Loans held for sale	191,723	290,467
Loans, net of allowance for credit losses	23,921,372	24,757,859
Accrued interest receivable	90,069	107,601
Mortgage servicing rights	65,620	43,820
Interest rate swap - non-designated hedge	408,776	802,763
Other derivative financial instruments (mortgage banking related)	5,966	11,136
Financial liabilities:
Deposits	35,050,516	30,719,416
Federal funds purchased and securities sold under agreements to repurchase	781,239	779,666
Other borrowings	334,640	386,126
Accrued interest payable	3,345	7,103
Interest rate swap - non-designated hedge	410,137	804,832
Commitments to extend credit \| Fair Value
Financial liabilities:
Commitments to extend credit	93,501	136,726
Quoted Prices In Active Markets for Identical Assets (Level 1)
Financial assets:
Cash and cash equivalents	6,843,147	4,609,255
Investment securities	160,568	160,443
Significant Other Observable Inputs (Level 2)
Financial assets:
Trading securities	77,689	10,674
Investment securities	6,971,542	4,287,857
Loans held for sale	191,723	290,467
Accrued interest receivable	19,241	12,952
Interest rate swap - non-designated hedge	408,776	802,763
Other derivative financial instruments (mortgage banking related)	5,966	11,136
Financial liabilities:
Deposits	35,050,516	30,719,416
Federal funds purchased and securities sold under agreements to repurchase	781,239	779,666
Other borrowings	334,640	386,126
Accrued interest payable	3,345	7,103
Interest rate swap - non-designated hedge	410,137	804,832
Significant Other Observable Inputs (Level 2) \| Commitments to extend credit
Financial liabilities:
Commitments to extend credit	93,501	136,726
Significant Unobservable Inputs (Level 3)
Financial assets:
Loans, net of allowance for credit losses	23,921,372	24,757,859
Accrued interest receivable	70,828	94,649
Mortgage servicing rights	$ 65,620	$ 43,820

Fair value of accrued interest payable as on date.

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Fair value portion of arrangements to extend credit.

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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 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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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 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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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.

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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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