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, 2019	Dec. 31, 2018
Financial Assets:
Investment securities held to maturity, Fair Value	$ 124,904	$ 150,932
Investment securities held to maturity, Carrying Value	123,975	153,646
Federal Home Loan Bank and other membership bank stocks, Fair Value	22,505	13,301
Federal Home Loan Bank and other membership bank stocks, Carrying Value	22,505	13,301
Loans and leases, net Fair Value	5,194,065	4,341,477
Loans and leases, net Carrying Value	5,097,820	4,419,045
Financial Liabilities:
Certificates of deposit, Fair Value	871,418	750,801
Certificates of deposit, Carrying value	870,804	757,038
Other borrowings, Fair Value	166,505	176,921
Other borrowings, Carrying value	165,816	181,118
Subordinated debentures, Fair Value	117,992	102,497
Subordinated debentures, Carrying Value	118,220	105,027
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 and leases, net Fair Value	0	0
Financial Liabilities:
Certificates of deposit, Fair Value	0	0
Other borrowings, Fair Value	0	0
Significant Other Observable Inputs (Level 2)
Financial Assets:
Investment securities held to maturity, Fair Value	121,503	143,913
Federal Home Loan Bank and other membership bank stocks, Fair Value	22,505	13,301
Loans and leases, net Fair Value	0	0
Financial Liabilities:
Certificates of deposit, Fair Value	871,418	750,801
Other borrowings, Fair Value	166,505	176,921
Significant Unobservable Inputs (Level 3)
Financial Assets:
Investment securities held to maturity, Fair Value	3,401	7,019
Federal Home Loan Bank and other membership bank stocks, Fair Value	0	0
Loans and leases, net Fair Value	5,194,065	4,341,477
Financial Liabilities:
Certificates of deposit, Fair Value	0	0
Other borrowings, Fair Value	0	0
Subordinated debentures, Fair Value	$ 117,992	$ 102,497

Certificate of deposits fair value disclosure.

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

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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 investments in Federal Home Loan Bank (FHLBank) stock.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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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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