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v3.3.1.900

Weighted average assumptions (Details 5) | 12 Months Ended
--- | ---
Dec. 31, 2015 | Dec. 31, 2014
Pension Benefits |  |
Used to determine benefit obligation |  |
Discount rate | 4.00% | 3.70%
Expected return on plan assets | 6.75% | 7.00%
Used to determine benefit cost |  |
Discount rate | 3.70% | 4.53%
Expected return on plan assets | 7.00% | 7.00%
Other Postretirement Benefits |  |
Used to determine benefit obligation |  |
Discount rate | 4.06% | 3.74%
Expected return on plan assets | 5.75% | 6.00%
Rate of compensation increase | 3.00% | 3.00%
Used to determine benefit cost |  |
Discount rate | 3.74% | 4.48%
Expected return on plan assets | 6.00% | 6.00%
Rate of compensation increase | 3.00% | 3.00%

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- Definition The interest rate used to adjust for the time value of money for the plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(1) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 + Details
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- Definition Expected rate of compensation increases (for pay-related plans). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(2) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 + Details
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