XML 44 R32.htm IDEA: XBRL DOCUMENT v3.7.0.1
Employee Benefit Plans - Narrative (Details)
3 Months Ended 6 Months Ended 12 Months Ended
Jun. 30, 2017
USD ($)
entrant
Jun. 30, 2016
USD ($)
Jun. 30, 2017
USD ($)
entrant
Jun. 30, 2016
USD ($)
Dec. 31, 2017
USD ($)
Defined Benefit Plan Disclosure [Line Items]          
Number of new entrants after pension plans were frozen | entrant 0   0    
Minimum | Forecast          
Defined Benefit Plan Disclosure [Line Items]          
Unrecognized actuarial losses         $ 17,000,000
Maximum | Forecast          
Defined Benefit Plan Disclosure [Line Items]          
Unrecognized actuarial losses         19,000,000
Other Post-Retirement Benefits          
Defined Benefit Plan Disclosure [Line Items]          
Net period benefit costs (less than) $ 100,000 $ 100,000 $ 100,000 $ 100,000  
Expected employer contributions for current year 200,000   200,000    
Pension Benefits          
Defined Benefit Plan Disclosure [Line Items]          
Net period benefit costs (less than) 300,000 0 600,000 0  
Employer contributions to the pension plans $ 0 $ 0 $ 0 $ 0  
Pension Benefits | Minimum | Forecast          
Defined Benefit Plan Disclosure [Line Items]          
Accumulated benefits         4,000,000
Pension Benefits | Maximum | Forecast          
Defined Benefit Plan Disclosure [Line Items]          
Accumulated benefits         $ 6,000,000