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, 2021	Dec. 31, 2020
Financial Assets:
Investment securities held to maturity, carrying value	$ 824,956	$ 90,766
Investment securities held to maturity, fair value	815,211	93,868
Federal Home Loan Bank and other membership stock, at cost	9,049	11,979
Federal Home Loan Bank and other membership bank stocks, Fair Value	9,049	11,979
Loans, net, Carrying Value	5,918,101	5,950,108
Loans, net, Fair Value	5,900,876	5,939,413
Financial Liabilities:
Certificates of deposit, Carrying Value	759,227	1,078,256
Certificates of deposit, Fair Value	753,483	1,077,620
Other borrowings, Carrying Value	25,000	25,000
Other borrowings, Fair Value	24,604	25,206
Subordinate debentures, Carrying Value	179,043	118,257
Subordinated debentures, Fair Value	175,243	118,208
U.S. Treasury and U.S. government agencies
Financial Assets:
Investment securities held to maturity, carrying value	18,672	25,565
Investment securities held to maturity, fair value	18,965	26,344
Mortgage-backed securities, residential
Financial Assets:
Investment securities held to maturity, carrying value	370,247	39,276
Investment securities held to maturity, fair value	364,976	40,733
Collateralized mortgage obligations, residential
Financial Assets:
Investment securities held to maturity, carrying value	13,921	14,590
Investment securities held to maturity, fair value	14,089	15,122
Mortgage-backed securities, multifamily
Financial Assets:
Investment securities held to maturity, carrying value	2,710	705
Investment securities held to maturity, fair value	2,734	759
Collateralized mortgage obligations, multifamily
Financial Assets:
Investment securities held to maturity, carrying value	0
Investment securities held to maturity, fair value	0
Obligations of states and political subdivisions
Financial Assets:
Investment securities held to maturity, carrying value	416,566	10,630
Investment securities held to maturity, fair value	411,576	10,910
Corporate debt securities
Financial Assets:
Investment securities held to maturity, carrying value	2,840
Investment securities held to maturity, fair value	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) \| Collateralized mortgage obligations, multifamily
Financial Assets:
Investment securities held to maturity, fair value	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
Significant Other Observable Inputs (Level 2)
Financial Assets:
Investment securities held to maturity, fair value	814,379	93,868
Federal Home Loan Bank and other membership bank stocks, Fair Value	9,049	11,979
Loans, net, Fair Value	0	0
Financial Liabilities:
Certificates of deposit, Fair Value	753,483	1,077,620
Other borrowings, Fair Value	24,604	25,206
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	18,965	26,344
Significant Other Observable Inputs (Level 2) \| Mortgage-backed securities, residential
Financial Assets:
Investment securities held to maturity, fair value	364,976	40,733
Significant Other Observable Inputs (Level 2) \| Collateralized mortgage obligations, residential
Financial Assets:
Investment securities held to maturity, fair value	14,089	15,122
Significant Other Observable Inputs (Level 2) \| Mortgage-backed securities, multifamily
Financial Assets:
Investment securities held to maturity, fair value	2,734	759
Significant Other Observable Inputs (Level 2) \| Collateralized mortgage obligations, multifamily
Financial Assets:
Investment securities held to maturity, fair value	0
Significant Other Observable Inputs (Level 2) \| Obligations of states and political subdivisions
Financial Assets:
Investment securities held to maturity, fair value	410,744	10,910
Significant Other Observable Inputs (Level 2) \| Corporate debt securities
Financial Assets:
Investment securities held to maturity, fair value	2,871
Significant Unobservable Inputs (Level 3)
Financial Assets:
Investment securities held to maturity, fair value	832	0
Federal Home Loan Bank and other membership bank stocks, Fair Value	0	0
Loans, net, Fair Value	5,900,876	5,939,413
Financial Liabilities:
Certificates of deposit, Fair Value	0	0
Other borrowings, Fair Value	0	0
Subordinated debentures, Fair Value	175,243	118,208
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) \| Collateralized mortgage obligations, multifamily
Financial Assets:
Investment securities held to maturity, fair value	0
Significant Unobservable Inputs (Level 3) \| Obligations of states and political subdivisions
Financial Assets:
Investment securities held to maturity, fair value	832	$ 0
Significant Unobservable Inputs (Level 3) \| Corporate debt securities
Financial Assets:
Investment securities held to maturity, fair value	$ 0

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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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Amount, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement.

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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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