Fair Value of Financial Instruments - Carrying Value and Estimated Fair Values of Financial Instruments Not Measured at Fair Value (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities held to maturity	$ 5,448	$ 25,117
Carrying Value \| Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	323,920	705,618
Carrying Value \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Non-marketable equity securities held in other financial institutions	76,822	45,192
Accrued interest and loan fees receivable	24,277	23,402
Deposits	6,303,158	6,570,693
FHLB advances and other borrowings	894,581	309,801
Subordinated indebtedness	157,540	157,417
Accrued interest payable	2,460	2,696
Carrying Value \| Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities held to maturity	4,288	22,767
LHFI , net	5,464,970	5,166,745
Estimated Fair Value \| Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	323,920	705,618
Estimated Fair Value \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Non-marketable equity securities held in other financial institutions	76,822	45,192
Accrued interest and loan fees receivable	24,277	23,402
Deposits	6,293,928	6,572,215
FHLB advances and other borrowings	846,980	305,374
Subordinated indebtedness	147,836	156,629
Accrued interest payable	2,460	2,696
Estimated Fair Value \| Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities held to maturity	5,448	25,117
LHFI , net	$ 5,421,977	$ 5,133,257

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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- Definition

Junior Subordinated Debenture Owed to Unconsolidated Subsidiary Trust, Fair Value

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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.

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-Publisher FASB
-Name Accounting Standards Codification
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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.

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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
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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