XML 131 R101.htm IDEA: XBRL DOCUMENT v3.6.0.2
EMPLOYEE BENEFIT PLANS EMPLOYEE BENEFIT PLANS - Narrative (Details)
 12 Months Ended
Aug. 01, 2014
USD ($)
Dec. 31, 2016
USD ($)
acquisition
employee
Dec. 31, 2015
USD ($)
acquisition
Dec. 31, 2014
USD ($)
Dec. 31, 2011
acquisition
Apr. 30, 2015
USD ($)
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]            
Non-elective contribution by employer as percentage of gross annual wages (percent)   3.00%        
Matching contribution by employer (percent)   100.00%        
Percentage of gross annual wages matched by employer (percent)   4.00%        
Expense under the plan   $ 3,900,000 $ 3,600,000 $ 3,000,000    
Number of significant acquisitions completed (acquisition) | acquisition   3 2   2  
Hampden Bancorp Inc            
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]            
Split-dollar agreement, accrued liability   $ 1,200,000       $ 860,000
Fixed Income Funds            
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]            
Target plan asset allocation (percent)   36.00%        
Marketable equity securities            
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]            
Target plan asset allocation (percent)   63.00%        
Cash and Cash Equivalents            
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]            
Target plan asset allocation (percent)   1.00%        
Pension Plans            
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]            
Number of employees participation (employee) | employee   0        
Net actuarial (gain) loss   $ 1,500,000 $ 2,000,000      
Expected cash contributions by employer   0        
Amount expected to be amortized from other comprehensive income into net periodic pension cost over the next fiscal year   100,000        
Defined benefit plan, fair value of plan assets   5,121,000 5,211,000 5,756,000    
Transfers between Level 1, 2, and 3   $ 0 $ 0      
Discount rate (percent)   4.17% 3.82%      
Pension Plans | Level 3            
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]            
Defined benefit plan, fair value of plan assets   $ 0 $ 0      
Pension Plans | Fixed Income Funds            
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]            
Defined benefit plan, fair value of plan assets   1,378,000 1,564,000      
Postretirement Benefits            
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]            
Net actuarial (gain) loss   (126,000) (257,000)      
Amount expected to be amortized from other comprehensive income into net periodic pension cost over the next fiscal year   83,000        
Defined benefit plan, fair value of plan assets   0 0 0    
Prior service cost of long-term care plan participants $ 558,000 $ 0 $ 1,595,000      
Discount rate (percent)   3.91% 4.15%      
Assumed health care cost trend rate (percent)   8.15%        
Assumed health care cost trend rate in 2020 (percent)   3.89%        
Supplemental Employee Retirement Plan            
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]            
Eligible age for retirement plan   62 years        
Accrued liability for other plans   $ 7,400,000 $ 6,500,000      
Other plans expense   917,000 $ 752,000 $ 583,000    
Supplemental Employee Retirement Plan | Hampden Bancorp Inc            
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]            
Accrued liability for other plans   $ 1,200,000       $ 1,400,000