Quarterly report pursuant to Section 13 or 15(d)

Loans and Leases - Analysis of Past Due Loans, Disaggregated by Loan Class, PCI (Detail) (Details)

v3.8.0.1
Loans and Leases - Analysis of Past Due Loans, Disaggregated by Loan Class, PCI (Detail) (Details) - USD ($)
$ in Thousands
Sep. 30, 2017
Jun. 30, 2017
Dec. 31, 2016
Sep. 30, 2016
Jun. 30, 2016
Dec. 31, 2015
Financing Receivable, Recorded Investment, Past Due [Line Items]            
Total Loans and leases receivable $ 4,195,355   $ 3,844,769      
Allowance 32,492   32,429      
Loans and leases receivable, net 4,162,863   3,812,340      
Real estate loans [Member]            
Financing Receivable, Recorded Investment, Past Due [Line Items]            
Total Loans and leases receivable 3,539,558   3,278,375      
Real estate loans [Member] | Hospitality [Member]            
Financing Receivable, Recorded Investment, Past Due [Line Items]            
Total Loans and leases receivable 733,226   651,158      
Real estate loans [Member] | Gas station [Member]            
Financing Receivable, Recorded Investment, Past Due [Line Items]            
Total Loans and leases receivable 247,430   262,879      
Real estate loans [Member] | Residential property [Member]            
Financing Receivable, Recorded Investment, Past Due [Line Items]            
Total Loans and leases receivable 430,627   338,767      
Commercial and industrial loans [Member]            
Financing Receivable, Recorded Investment, Past Due [Line Items]            
Total Loans and leases receivable 364,456   300,220      
Commercial and industrial loans [Member] | Commercial term [Member]            
Financing Receivable, Recorded Investment, Past Due [Line Items]            
Total Loans and leases receivable 170,942   138,168      
Consumer loans [Member]            
Financing Receivable, Recorded Investment, Past Due [Line Items]            
Total Loans and leases receivable 19,070   22,880      
PCI Loans and Leases [Member]            
Financing Receivable, Recorded Investment, Past Due [Line Items]            
Past due loans and leases receivable 1,273   1,392      
Current 7,431   8,471      
Total Loans and leases receivable 8,704   9,863 $ 15,540    
Allowance 794 $ 720 971 5,533 $ 5,448 $ 5,441
Loans and leases receivable, net 7,910   8,892 $ 10,007   $ 14,573
PCI Loans and Leases [Member] | Real estate loans [Member]            
Financing Receivable, Recorded Investment, Past Due [Line Items]            
Past due loans and leases receivable 1,268   1,336      
Current 7,342   8,341      
Total Loans and leases receivable 8,610   9,677      
Allowance 752   922      
Loans and leases receivable, net 7,858   8,755      
PCI Loans and Leases [Member] | Real estate loans [Member] | Hospitality [Member]            
Financing Receivable, Recorded Investment, Past Due [Line Items]            
Total Loans and leases receivable 1,664   1,618      
PCI Loans and Leases [Member] | Real estate loans [Member] | Gas station [Member]            
Financing Receivable, Recorded Investment, Past Due [Line Items]            
Total Loans and leases receivable 2,388   2,692      
PCI Loans and Leases [Member] | Real estate loans [Member] | Residential property [Member]            
Financing Receivable, Recorded Investment, Past Due [Line Items]            
Total Loans and leases receivable 958   976      
PCI Loans and Leases [Member] | Commercial and industrial loans [Member]            
Financing Receivable, Recorded Investment, Past Due [Line Items]            
Past due loans and leases receivable 5   6      
Current 46   130      
Total Loans and leases receivable 51   136      
Allowance 41   41      
Loans and leases receivable, net 10   95      
PCI Loans and Leases [Member] | Commercial and industrial loans [Member] | Commercial term [Member]            
Financing Receivable, Recorded Investment, Past Due [Line Items]            
Total Loans and leases receivable 51   136      
PCI Loans and Leases [Member] | Consumer loans [Member]            
Financing Receivable, Recorded Investment, Past Due [Line Items]            
Past due loans and leases receivable 0   50      
Current 43   0      
Total Loans and leases receivable 43   50      
Allowance 1   8      
Loans and leases receivable, net 42   42      
PCI Loans and Leases [Member] | 30-59 Days Past Due            
Financing Receivable, Recorded Investment, Past Due [Line Items]            
Past due loans and leases receivable 689   975      
PCI Loans and Leases [Member] | 30-59 Days Past Due | Real estate loans [Member]            
Financing Receivable, Recorded Investment, Past Due [Line Items]            
Past due loans and leases receivable 689   975      
PCI Loans and Leases [Member] | 30-59 Days Past Due | Commercial and industrial loans [Member]            
Financing Receivable, Recorded Investment, Past Due [Line Items]            
Past due loans and leases receivable 0   0      
PCI Loans and Leases [Member] | 30-59 Days Past Due | Consumer loans [Member]            
Financing Receivable, Recorded Investment, Past Due [Line Items]            
Past due loans and leases receivable 0   0      
PCI Loans and Leases [Member] | 60-89 Days Past Due            
Financing Receivable, Recorded Investment, Past Due [Line Items]            
Past due loans and leases receivable 0   0      
PCI Loans and Leases [Member] | 60-89 Days Past Due | Real estate loans [Member]            
Financing Receivable, Recorded Investment, Past Due [Line Items]            
Past due loans and leases receivable 0   0      
PCI Loans and Leases [Member] | 60-89 Days Past Due | Commercial and industrial loans [Member]            
Financing Receivable, Recorded Investment, Past Due [Line Items]            
Past due loans and leases receivable 0   0      
PCI Loans and Leases [Member] | 60-89 Days Past Due | Consumer loans [Member]            
Financing Receivable, Recorded Investment, Past Due [Line Items]            
Past due loans and leases receivable 0   0      
PCI Loans and Leases [Member] | 90 Days or More Past Due            
Financing Receivable, Recorded Investment, Past Due [Line Items]            
Past due loans and leases receivable 584   417      
PCI Loans and Leases [Member] | 90 Days or More Past Due | Real estate loans [Member]            
Financing Receivable, Recorded Investment, Past Due [Line Items]            
Past due loans and leases receivable 579   361      
PCI Loans and Leases [Member] | 90 Days or More Past Due | Commercial and industrial loans [Member]            
Financing Receivable, Recorded Investment, Past Due [Line Items]            
Past due loans and leases receivable 5   6      
PCI Loans and Leases [Member] | 90 Days or More Past Due | Consumer loans [Member]            
Financing Receivable, Recorded Investment, Past Due [Line Items]            
Past due loans and leases receivable $ 0   $ 50