XML 63 R51.htm IDEA: XBRL DOCUMENT v3.5.0.2
Commitments (Details) - USD ($)
$ in Thousands
 9 Months Ended
Sep. 30, 2016
Jun. 30, 2016
Dec. 31, 2015
Schedule of Commitments [Line Items]      
Unadvanced commitments on impaired loans $ 500   $ 0
Commitments to extend credit      
Schedule of Commitments [Line Items]      
Off-balance sheet financial instruments, contractual amounts 1,086,372   1,140,028
Standby letters of credit      
Schedule of Commitments [Line Items]      
Off-balance sheet financial instruments, contractual amounts $ 64,360   54,648
Standby letters of credit | Maximum      
Schedule of Commitments [Line Items]      
Remaining term 5 years    
Standby letters of credit | Minimum      
Schedule of Commitments [Line Items]      
Remaining term 1 month    
Unadvanced Commitment on Impaired Loan      
Schedule of Commitments [Line Items]      
Estimated losses attributable to unadvanced commitments on impaired loans   $ 300 300
Fixed Rate Loan Commitment | Commitments to extend credit      
Schedule of Commitments [Line Items]      
Off-balance sheet financial instruments, contractual amounts $ 107,500   $ 93,900