Fair Value Measurements - Estimated Fair Values and Related Carrying Amounts of Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity securities, net	$ 1,517,378	$ 341,925
Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	1,650,653	3,472,152
Interest bearing balances due from banks - time	1,882	1,579
Held-to-maturity securities, net	1,529,221	333,031
Interest receivable	72,990	72,597
Federal funds purchased and securities sold under agreements to repurchase	185,403	299,111
Other borrowings	1,337,973	1,342,067
Subordinated notes and debentures	384,131	382,874
Interest payable	6,759	8,887
Carrying Amount \| Non-interest bearing transaction accounts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Deposits	5,325,318	4,482,091
Carrying Amount \| Interest bearing transaction accounts and savings deposits
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Deposits	11,588,770	9,672,608
Carrying Amount \| Time deposits
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Deposits	2,452,460	2,832,327
Carrying Amount \| Loans, net
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans, net	11,807,171	12,662,847
Fair Value Measurements
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	1,650,653	3,472,152
Interest bearing balances due from banks - time	1,882	1,579
Held-to-maturity securities, net	1,517,378	341,925
Interest receivable	72,990	72,597
Federal funds purchased and securities sold under agreements to repurchase	185,403	299,111
Other borrowings	1,393,711	1,448,625
Subordinated notes and debentures	394,464	398,827
Interest payable	6,759	8,887
Fair Value Measurements \| Non-interest bearing transaction accounts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Deposits	5,325,318	4,482,091
Fair Value Measurements \| Interest bearing transaction accounts and savings deposits
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Deposits	11,588,770	9,672,608
Fair Value Measurements \| Time deposits
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Deposits	2,451,055	2,848,621
Fair Value Measurements \| Loans, net
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans, net	11,922,735	12,736,991
Fair Value Measurements \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	1,650,653	3,472,152
Interest bearing balances due from banks - time	0	0
Held-to-maturity securities, net	0	0
Interest receivable	0	0
Federal funds purchased and securities sold under agreements to repurchase	0	0
Other borrowings	0	0
Subordinated notes and debentures	0	0
Interest payable	0	0
Fair Value Measurements \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Non-interest bearing transaction accounts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Deposits	0	0
Fair Value Measurements \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Interest bearing transaction accounts and savings deposits
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Deposits	0	0
Fair Value Measurements \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Time deposits
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Deposits	0	0
Fair Value Measurements \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Loans, net
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans, net	0	0
Fair Value Measurements \| Significant Other Observable Inputs (Level 2)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	0	0
Interest bearing balances due from banks - time	1,882	1,579
Held-to-maturity securities, net	1,517,378	341,925
Interest receivable	72,990	72,597
Federal funds purchased and securities sold under agreements to repurchase	185,403	299,111
Other borrowings	1,393,711	1,448,625
Subordinated notes and debentures	394,464	398,827
Interest payable	6,759	8,887
Fair Value Measurements \| Significant Other Observable Inputs (Level 2) \| Non-interest bearing transaction accounts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Deposits	5,325,318	4,482,091
Fair Value Measurements \| Significant Other Observable Inputs (Level 2) \| Interest bearing transaction accounts and savings deposits
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Deposits	11,588,770	9,672,608
Fair Value Measurements \| Significant Other Observable Inputs (Level 2) \| Time deposits
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Deposits	0	0
Fair Value Measurements \| Significant Other Observable Inputs (Level 2) \| Loans, net
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans, net	0	0
Fair Value Measurements \| Significant Unobservable Inputs (Level 3)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	0	0
Interest bearing balances due from banks - time	0	0
Held-to-maturity securities, net	0	0
Interest receivable	0	0
Federal funds purchased and securities sold under agreements to repurchase	0	0
Other borrowings	0	0
Subordinated notes and debentures	0	0
Interest payable	0	0
Fair Value Measurements \| Significant Unobservable Inputs (Level 3) \| Non-interest bearing transaction accounts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Deposits	0	0
Fair Value Measurements \| Significant Unobservable Inputs (Level 3) \| Interest bearing transaction accounts and savings deposits
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Deposits	0	0
Fair Value Measurements \| Significant Unobservable Inputs (Level 3) \| Time deposits
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Deposits	2,451,055	2,848,621
Fair Value Measurements \| Significant Unobservable Inputs (Level 3) \| Loans, net
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans, net	$ 11,922,735	$ 12,736,991

Represents the fair value portion of interest bearing balances due from banks - time.

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Fair value portion of interest payable on debt, including, but not limited to, trade payables.

+ References

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The fair value of accrued interest receivable.

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- Definition

The fair value portion of the aggregate of other miscellaneous borrowings owed by the reporting 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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- 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.

+ References

No definition available.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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- Definition

Fair value portion 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.

+ References

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- Definition

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Publisher FASB
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- Definition

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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-URI http://asc.fasb.org/subtopic&trid=2196772

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