XML 84 R52.htm IDEA: XBRL DOCUMENT v3.3.1.900
Employee Retirement Benefits - Assumptions Used for Periodic Income (Details) - Pension Benefits [Member]
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items]      
Discount rate 3.95% 4.80% 4.00%
Salary increase 4.10% 4.00% 4.00%
Expected long-term rate of return 7.75% 7.75% 7.75%
Expected long-term rate of return, net of management fees 7.35%