Quarterly report pursuant to Section 13 or 15(d)

Fair Value Measurements - Estimated Fair Values of Financial Instruments (Detail)

v3.7.0.1
Fair Value Measurements - Estimated Fair Values of Financial Instruments (Detail) - USD ($)
$ in Thousands
Mar. 31, 2017
Dec. 31, 2016
Financial assets:    
Cash and due from banks $ 138,592 $ 147,235
Securities available for sale 548,010 516,964
Accrued interest receivable 10,774 10,987
FRB stock 40,049 48,047
Financial liabilities:    
Noninterest-bearing deposits 1,241,272 1,203,240
Interest-bearing deposits 2,841,893 2,606,497
Accrued interest payable 2,619 2,567
Carrying Amount [Member]    
Financial assets:    
Cash and due from banks 138,592 147,235
Securities available for sale 548,010 516,964
Loans and leases receivable, net of allowance for loan and lease losses 3,910,799 3,812,340
Loans held for sale 8,849 9,316
Accrued interest receivable 10,774 10,987
FHLB stock 16,385 16,385
Financial liabilities:    
Noninterest-bearing deposits 1,241,272 1,203,240
Interest-bearing deposits 2,841,893 2,606,497
Borrowings 166,795 333,978
Accrued interest payable 2,619 2,567
Off-balance sheet items:    
Commitments to extend credit 330,906 310,987
Letters of credit   15,669
Carrying Amount [Member] | Standby letters of credit [Member]    
Off-balance sheet items:    
Letters of credit 20,555  
Fair Value, Inputs, Level 1 [Member] | Fair Value [Member]    
Financial assets:    
Cash and due from banks 138,592 147,235
Securities available for sale   22,550
Loans and leases receivable, net of allowance for loan and lease losses 0 0
Loans held for sale 0 0
Accrued interest receivable 10,774 10,987
FHLB stock 0 0
Financial liabilities:    
Noninterest-bearing deposits 0 0
Interest-bearing deposits 0 0
Borrowings 0 0
Accrued interest payable 2,619 2,567
Off-balance sheet items:    
Commitments to extend credit 0 0
Letters of credit   0
Fair Value, Inputs, Level 1 [Member] | Fair Value [Member] | Standby letters of credit [Member]    
Off-balance sheet items:    
Letters of credit 0  
Fair Value, Inputs, Level 2 [Member] | Fair Value [Member]    
Financial assets:    
Cash and due from banks 0 0
Securities available for sale   494,414
Loans and leases receivable, net of allowance for loan and lease losses 0 0
Loans held for sale 8,849 9,316
Accrued interest receivable 0 0
FHLB stock 16,385 16,385
Financial liabilities:    
Noninterest-bearing deposits 1,241,272 1,203,240
Interest-bearing deposits 0 0
Borrowings 0 0
Accrued interest payable 0 0
Off-balance sheet items:    
Commitments to extend credit 0 0
Letters of credit   0
Fair Value, Inputs, Level 2 [Member] | Fair Value [Member] | Standby letters of credit [Member]    
Off-balance sheet items:    
Letters of credit 0  
Fair Value, Inputs, Level 3 [Member] | Fair Value [Member]    
Financial assets:    
Cash and due from banks 0 0
Securities available for sale   0
Loans and leases receivable, net of allowance for loan and lease losses 3,877,761 3,789,579
Loans held for sale 0 0
Accrued interest receivable 0 0
FHLB stock 0 0
Financial liabilities:    
Noninterest-bearing deposits 0 0
Interest-bearing deposits 2,789,454 2,541,929
Borrowings 166,795 333,978
Accrued interest payable 0 0
Off-balance sheet items:    
Commitments to extend credit 330,906 310,987
Letters of credit   $ 15,669
Fair Value, Inputs, Level 3 [Member] | Fair Value [Member] | Standby letters of credit [Member]    
Off-balance sheet items:    
Letters of credit $ 20,555