Annual report pursuant to Section 13 and 15(d)

Loans - Troubled Debt Restructurings, Disaggregated by Type of Concession and by Loan Type (Detail)

v3.3.1.900
Loans - Troubled Debt Restructurings, Disaggregated by Type of Concession and by Loan Type (Detail) - USD ($)
$ in Thousands
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Financing Receivable, Modifications [Line Items]      
Non-Accrual TDRs, Deferral of Principal $ 3,131 $ 4,116 $ 3,786
Non-Accrual TDRs, Deferral of Principal and Interest 1,329 1,444 2,243
Non-Accrual TDRs, Reduction of Principal and Interest 1,329 3,246 2,733
Non-Accrual TDRs, Extension of Maturity 1,089 3,650 1,774
Non-Accrual TDRs, Total 6,878 12,456 10,536
Accrual TDRs, Deferral of Principal 4,241 9,004 5,524
Accrual TDRs, Deferral of Principal and Interest 214 226 0
Accrual TDRs, Reduction of Principal and Interest 3,222 1,549 4,966
Accrual TDRs, Extension of Maturity 2,622 3,038 8,927
Accrual TDRs 10,299 13,817 19,417
Real estate loans [Member] | Retail [Member]      
Financing Receivable, Modifications [Line Items]      
Non-Accrual TDRs, Deferral of Principal 0 0 0
Non-Accrual TDRs, Deferral of Principal and Interest 0 0 0
Non-Accrual TDRs, Reduction of Principal and Interest 0 0 0
Non-Accrual TDRs, Extension of Maturity 344 2,032 750
Non-Accrual TDRs, Total 344 2,032 750
Accrual TDRs, Deferral of Principal 0 306 0
Accrual TDRs, Deferral of Principal and Interest 0 0 0
Accrual TDRs, Reduction of Principal and Interest 1,227 0 0
Accrual TDRs, Extension of Maturity 0 0 474
Accrual TDRs 1,227 306 474
Real estate loans [Member] | Hotel/motel [Member]      
Financing Receivable, Modifications [Line Items]      
Non-Accrual TDRs, Deferral of Principal 1,216 1,115 1,272
Non-Accrual TDRs, Deferral of Principal and Interest 28 (53) 758
Non-Accrual TDRs, Reduction of Principal and Interest 0 0 0
Non-Accrual TDRs, Extension of Maturity 0 0 0
Non-Accrual TDRs, Total 1,244 1,062 2,030
Accrual TDRs, Deferral of Principal 414 1,807 1,000
Accrual TDRs, Deferral of Principal and Interest 0 0 0
Accrual TDRs, Reduction of Principal and Interest 0 0 0
Accrual TDRs, Extension of Maturity 0 0 0
Accrual TDRs 414 1,807 1,000
Real estate loans [Member] | Gas station [Member]      
Financing Receivable, Modifications [Line Items]      
Non-Accrual TDRs, Deferral of Principal 959 1,075 1,291
Non-Accrual TDRs, Deferral of Principal and Interest 0 0 0
Non-Accrual TDRs, Reduction of Principal and Interest 0 0 729
Non-Accrual TDRs, Extension of Maturity 0 0 0
Non-Accrual TDRs, Total 959 1,075 2,020
Accrual TDRs, Deferral of Principal 0 2,335 365
Accrual TDRs, Deferral of Principal and Interest 0 0 0
Accrual TDRs, Reduction of Principal and Interest 0 0 0
Accrual TDRs, Extension of Maturity 0 0 2,609
Accrual TDRs 0 2,335 2,974
Real estate loans [Member] | Other [Member]      
Financing Receivable, Modifications [Line Items]      
Non-Accrual TDRs, Deferral of Principal 0 943 403
Non-Accrual TDRs, Deferral of Principal and Interest 1,301 1,498 1,279
Non-Accrual TDRs, Reduction of Principal and Interest 216 433 555
Non-Accrual TDRs, Extension of Maturity 8 24 0
Non-Accrual TDRs, Total 1,525 2,898 2,237
Accrual TDRs, Deferral of Principal 3,537 2,343 2,956
Accrual TDRs, Deferral of Principal and Interest 0 0 0
Accrual TDRs, Reduction of Principal and Interest 322 782 1,253
Accrual TDRs, Extension of Maturity 1,378 1,372 2,027
Accrual TDRs 5,237 4,497 6,236
Real estate loans [Member] | Residential property [Member]      
Financing Receivable, Modifications [Line Items]      
Non-Accrual TDRs, Deferral of Principal 689 742 795
Non-Accrual TDRs, Deferral of Principal and Interest 0 0 0
Non-Accrual TDRs, Reduction of Principal and Interest 0 0 0
Non-Accrual TDRs, Extension of Maturity 0 0 0
Non-Accrual TDRs, Total 689 742 795
Accrual TDRs, Deferral of Principal 0 0 0
Accrual TDRs, Deferral of Principal and Interest 0 0 0
Accrual TDRs, Reduction of Principal and Interest 0 0 0
Accrual TDRs, Extension of Maturity 299 308 0
Accrual TDRs 299 308 0
Commercial and industrial loans [Member] | Commercial term [Member]      
Financing Receivable, Modifications [Line Items]      
Non-Accrual TDRs, Deferral of Principal 45 14 25
Non-Accrual TDRs, Deferral of Principal and Interest 0 (1) 206
Non-Accrual TDRs, Reduction of Principal and Interest 997 2,556 1,449
Non-Accrual TDRs, Extension of Maturity 679 1,481 851
Non-Accrual TDRs, Total 1,721 4,050 2,531
Accrual TDRs, Deferral of Principal 40 57 1,203
Accrual TDRs, Deferral of Principal and Interest 214 226 0
Accrual TDRs, Reduction of Principal and Interest 1,673 567 2,286
Accrual TDRs, Extension of Maturity 945 1,358 3,817
Accrual TDRs 2,872 2,208 7,306
Commercial and industrial loans [Member] | Commercial lines of credit [Member]      
Financing Receivable, Modifications [Line Items]      
Non-Accrual TDRs, Deferral of Principal 222 227 0
Non-Accrual TDRs, Deferral of Principal and Interest 0 0 0
Non-Accrual TDRs, Reduction of Principal and Interest 0 126 0
Non-Accrual TDRs, Extension of Maturity 58 113 173
Non-Accrual TDRs, Total 280 466 173
Accrual TDRs, Deferral of Principal 0 2,156 0
Accrual TDRs, Deferral of Principal and Interest 0 0 0
Accrual TDRs, Reduction of Principal and Interest 0 0 191
Accrual TDRs, Extension of Maturity 0 0 0
Accrual TDRs 0 2,156 191
Commercial and industrial loans [Member] | International loans [Member]      
Financing Receivable, Modifications [Line Items]      
Non-Accrual TDRs, Deferral of Principal 0 0 0
Non-Accrual TDRs, Deferral of Principal and Interest 0 0 0
Non-Accrual TDRs, Reduction of Principal and Interest 0 0 0
Non-Accrual TDRs, Extension of Maturity 0 0 0
Non-Accrual TDRs, Total 0 0 0
Accrual TDRs, Deferral of Principal 0 0 0
Accrual TDRs, Deferral of Principal and Interest 0 0 0
Accrual TDRs, Reduction of Principal and Interest 0 200 1,087
Accrual TDRs, Extension of Maturity 0 0 0
Accrual TDRs 0 200 1,087
Consumer loans [Member]      
Financing Receivable, Modifications [Line Items]      
Non-Accrual TDRs, Deferral of Principal 0 0 0
Non-Accrual TDRs, Deferral of Principal and Interest 0 0 0
Non-Accrual TDRs, Reduction of Principal and Interest 116 131 0
Non-Accrual TDRs, Extension of Maturity 0 0 0
Non-Accrual TDRs, Total 116 131 0
Accrual TDRs, Deferral of Principal 250 0 0
Accrual TDRs, Deferral of Principal and Interest 0 0 0
Accrual TDRs, Reduction of Principal and Interest 0 0 149
Accrual TDRs, Extension of Maturity 0 0 0
Accrual TDRs $ 250 $ 0 $ 149