XML 77 R60.htm IDEA: XBRL DOCUMENT v3.6.0.2
Employee Benefit Plans - Summary of plan weighted average asset allocation by asset category along with target allocation for 2017 (Details 6) - Retirement Income Plan
12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]    
Percentage of Plan Assets 100.00% 100.00%
Cash and Cash Equivalents    
Defined Benefit Plan Disclosure [Line Items]    
Target Allocation for 2017 minimum percentage 0.00%  
Target Allocation for 2017 maximum percentage 5.00%  
Percentage of Plan Assets 3.30% 0.70%
Debt Securities - Core Fixed Income    
Defined Benefit Plan Disclosure [Line Items]    
Target Allocation for 2017 minimum percentage 15.00%  
Target Allocation for 2017 maximum percentage 50.00%  
Percentage of Plan Assets 25.30% 25.80%
Domestic Equity Securities    
Defined Benefit Plan Disclosure [Line Items]    
Target Allocation for 2017 minimum percentage 0.00%  
Target Allocation for 2017 maximum percentage 40.00%  
Percentage of Plan Assets 25.50% 27.60%
International Equity Securities    
Defined Benefit Plan Disclosure [Line Items]    
Target Allocation for 2017 minimum percentage 0.00%  
Target Allocation for 2017 maximum percentage 40.00%  
Percentage of Plan Assets 20.80% 19.10%
Investments measured at net asset value    
Defined Benefit Plan Disclosure [Line Items]    
Target Allocation for 2017 minimum percentage 0.00%  
Target Allocation for 2017 maximum percentage 20.00%  
Percentage of Plan Assets 25.10% 26.80%