Fair Value Measurement and Fair Value of Financial Instruments - Carrying Values and Fair Values of Company's Financial Instruments (Detail) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Financial Assets:
Investment securities held to maturity, carrying value	$ 923,308	$ 824,956
Investment securities held to maturity, fair value	760,455	815,211
Federal Home Loan Bank and other membership stock, at cost	42,483	9,049
Federal Home Loan Bank and other membership bank stocks, Fair Value	42,483	9,049
Loans, net, Carrying Value	7,795,786	5,918,101
Loans, net, Fair Value	7,561,997	5,900,876
Financial Liabilities:
Certificates of deposit, Carrying Value	1,208,177	759,227
Certificates of deposit, Fair Value	1,174,230	753,483
Other borrowings, Carrying Value	25,000	25,000
Other borrowings, Fair Value	23,001	24,604
Subordinate debentures, Carrying Value	194,264	179,043
Subordinated debentures, Fair Value	160,933	175,243
U.S. Treasury and U.S. government agencies
Financial Assets:
Investment securities held to maturity, carrying value	11,099	18,672
Investment securities held to maturity, fair value	10,385	18,965
Mortgage-backed securities, residential
Financial Assets:
Investment securities held to maturity, carrying value	360,683	370,247
Investment securities held to maturity, fair value	302,612	364,976
Collateralized mortgage obligations, residential
Financial Assets:
Investment securities held to maturity, carrying value	13,026	13,921
Investment securities held to maturity, fair value	10,456	14,089
Mortgage-backed securities, multifamily
Financial Assets:
Investment securities held to maturity, carrying value	5,094	2,710
Investment securities held to maturity, fair value	4,347	2,734
Obligations of states and political subdivisions
Financial Assets:
Investment securities held to maturity, carrying value	530,506	416,566
Investment securities held to maturity, fair value	430,108	411,576
Corporate debt securities
Financial Assets:
Investment securities held to maturity, carrying value	2,900	2,840
Investment securities held to maturity, fair value	2,547	2,871
Quoted Prices in Active Markets for Identical Assets (Level 1)
Financial Assets:
Investment securities held to maturity, fair value	0	0
Federal Home Loan Bank and other membership bank stocks, Fair Value	0	0
Loans, net, Fair Value	0	0
Financial Liabilities:
Certificates of deposit, Fair Value	0	0
Other borrowings, Fair Value	0	0
Subordinated debentures, Fair Value	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| U.S. Treasury and U.S. government agencies
Financial Assets:
Investment securities held to maturity, fair value	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Mortgage-backed securities, residential
Financial Assets:
Investment securities held to maturity, fair value	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Collateralized mortgage obligations, residential
Financial Assets:
Investment securities held to maturity, fair value	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Mortgage-backed securities, multifamily
Financial Assets:
Investment securities held to maturity, fair value	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Obligations of states and political subdivisions
Financial Assets:
Investment securities held to maturity, fair value	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Corporate debt securities
Financial Assets:
Investment securities held to maturity, fair value	0	0
Significant Other Observable Inputs (Level 2)
Financial Assets:
Investment securities held to maturity, fair value	758,982	814,379
Federal Home Loan Bank and other membership bank stocks, Fair Value	42,483	9,049
Loans, net, Fair Value	0	0
Financial Liabilities:
Certificates of deposit, Fair Value	1,174,230	753,483
Other borrowings, Fair Value	23,001	24,604
Subordinated debentures, Fair Value	0	0
Significant Other Observable Inputs (Level 2) \| U.S. Treasury and U.S. government agencies
Financial Assets:
Investment securities held to maturity, fair value	10,385	18,965
Significant Other Observable Inputs (Level 2) \| Mortgage-backed securities, residential
Financial Assets:
Investment securities held to maturity, fair value	302,612	364,976
Significant Other Observable Inputs (Level 2) \| Collateralized mortgage obligations, residential
Financial Assets:
Investment securities held to maturity, fair value	10,456	14,089
Significant Other Observable Inputs (Level 2) \| Mortgage-backed securities, multifamily
Financial Assets:
Investment securities held to maturity, fair value	4,347	2,734
Significant Other Observable Inputs (Level 2) \| Obligations of states and political subdivisions
Financial Assets:
Investment securities held to maturity, fair value	428,635	410,744
Significant Other Observable Inputs (Level 2) \| Corporate debt securities
Financial Assets:
Investment securities held to maturity, fair value	2,547	2,871
Significant Unobservable Inputs (Level 3)
Financial Assets:
Investment securities held to maturity, fair value	1,473	832
Federal Home Loan Bank and other membership bank stocks, Fair Value	0	0
Loans, net, Fair Value	7,561,997	5,900,876
Financial Liabilities:
Certificates of deposit, Fair Value	0	0
Other borrowings, Fair Value	0	0
Subordinated debentures, Fair Value	160,933	175,243
Significant Unobservable Inputs (Level 3) \| U.S. Treasury and U.S. government agencies
Financial Assets:
Investment securities held to maturity, fair value	0	0
Significant Unobservable Inputs (Level 3) \| Mortgage-backed securities, residential
Financial Assets:
Investment securities held to maturity, fair value	0	0
Significant Unobservable Inputs (Level 3) \| Collateralized mortgage obligations, residential
Financial Assets:
Investment securities held to maturity, fair value	0	0
Significant Unobservable Inputs (Level 3) \| Mortgage-backed securities, multifamily
Financial Assets:
Investment securities held to maturity, fair value	0	0
Significant Unobservable Inputs (Level 3) \| Obligations of states and political subdivisions
Financial Assets:
Investment securities held to maturity, fair value	1,473	832
Significant Unobservable Inputs (Level 3) \| Corporate debt securities
Financial Assets:
Investment securities held to maturity, fair value	$ 0	$ 0

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Other Borrowings Fair Value Disclosure

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Amount excluding accrued interest, after allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity).

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

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Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

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

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Fair value portion of an agreement for an unconditional promise by the maker to pay the holder a definite sum of money at a future date.

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Amortized cost, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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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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