Fair Value of Financial Instruments - Carrying Amount and Estimated Fair Value of Financial Instruments (Detail) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Financial assets
Cash and due from banks	$ 477,778	$ 187,203
Federal funds sold	29,993	16,547
Certificates of deposit with other banks	4,250	4,750
Loans held for sale	25,056	25,310
Loans and leases held for investment, net of allowance for credit losses on loans and leases	600,571	645,201
Carrying Amount
Financial assets
Cash and due from banks	477,778	187,203
Federal funds sold	29,993	16,547
Certificates of deposit with other banks	4,250	4,750
Loans held for sale	1,003,579	1,091,209
Loans and leases held for investment, net of allowance for credit losses on loans and leases	5,074,612	4,812,477
Financial liabilities
Deposits	7,637,163	7,112,044
Borrowings	196,911	318,289
Estimate of Fair Value Measurement
Financial assets
Cash and due from banks	477,778	187,203
Federal funds sold	29,993	16,547
Certificates of deposit with other banks	4,316	4,930
Loans held for sale	1,074,381	1,197,307
Loans and leases held for investment, net of allowance for credit losses on loans and leases	5,176,365	4,958,875
Financial liabilities
Deposits	7,247,748	6,942,512
Borrowings	188,221	312,036
Level 1 \| Estimate of Fair Value Measurement
Financial assets
Cash and due from banks	477,778	187,203
Federal funds sold	29,993	16,547
Certificates of deposit with other banks	4,316	4,930
Level 2 \| Estimate of Fair Value Measurement
Financial liabilities
Deposits	7,247,748	6,942,512
Level 3 \| Estimate of Fair Value Measurement
Financial assets
Loans held for sale	1,074,381	1,197,307
Loans and leases held for investment, net of allowance for credit losses on loans and leases	5,176,365	4,958,875
Financial liabilities
Borrowings	$ 188,221	$ 312,036

For banks and other depository institutions: Includes cash on hand (currency and coin), cash items in process of collection, noninterest bearing deposits due from other financial institutions (including corporate credit unions), and noninterest bearing balances with the Federal Reserve Banks, Federal Home Loan Banks and central banks.

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A savings certificate entitling the Entity (that is, bearer) to receive interest at an established maturity date, based upon a fixed interest rate. A certificate of deposit may be issued in any denomination. Certificates of deposit are generally issued by commercial banks and, therefore, insured by the FDIC (up to the prescribed limit). Certificates of deposit generally restrict holders from withdrawing funds on demand without the incurrence of penalties. Generally, only certificates of deposit with original maturities of three months or less qualify as cash equivalents. Original maturity means original maturity to the entity holding the investment. As a related example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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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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