Fair Value of Financial Instruments - Carrying Value and Estimated Fair Values of Financial Instruments Not Measured at Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities held to maturity	$ 25,117	$ 41,205
Carrying Value \| Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	705,618	377,214
Carrying Value \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Non-marketable equity securities held in other financial institutions	45,192	62,586
Accrued interest and loan fees receivable	23,402	27,146
Deposits	6,570,693	5,751,315
FHLB advances and other borrowings	309,801	984,608
Subordinated indebtedness	157,417	157,181
Accrued interest payable	2,696	3,556
Carrying Value \| Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities held to maturity	22,767	38,128
LHFI , net	5,166,745	5,621,092
Estimated Fair Value \| Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	705,618	377,214
Estimated Fair Value \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Non-marketable equity securities held in other financial institutions	45,192	62,586
Accrued interest and loan fees receivable	23,402	27,146
Deposits	6,572,215	5,756,312
FHLB advances and other borrowings	305,374	991,943
Subordinated indebtedness	156,629	156,395
Accrued interest payable	2,696	3,556
Estimated Fair Value \| Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities held to maturity	25,117	41,205
LHFI , net	$ 5,133,257	$ 5,802,744

Accrued Fees and Other Revenue Receivable, Fair Value

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- Definition

Federal Home Loan Bank Advances and Securities Sold Under Agreements to Repurchase, Fair Value

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No definition available.

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- Definition

Junior Subordinated Debenture Owed to Unconsolidated Subsidiary Trust, Fair Value

+ References

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- Definition

Loans and Leases Receivable, Net of Deferred Income, Fair Value Disclosure

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- Definition

Other Investments, Fair Value

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- Definition

Fair value portion of accrued expenses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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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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- 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
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aa)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=123581744&loc=SL120269820-111563

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