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Employee Benefits - Expected Rate of Return, Investment Policy, and Multiemployer Plans - Narrative (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2016 USD ($) payment defined_contribution_plan
Asset allocation structure of the portfolio |
Compound annualized risk free rate | 3.50%
Expected overall portfolio return percentage | 8.87%
Percentage of estimated expense | 0.39%
Net long term rate of return | 8.48%
Number of minimum quarterly cash contributions during fiscal 2016 and 2017 | payment | 4
Minimum required contribution for plan year, per quarter cash contributions during fiscal - 2016 | $ | $ 3.6
Percentages of employees represented by various labor unions | 35.00%
Percentage of collective bargaining agreements up for renewal in 2016 | 10.00%
Number of defined contribution plans | defined_contribution_plan | 2
Equities |
Asset allocation structure of the portfolio |
Asset allocation structure of the portfolio | 61.00%
Equity securities — domestic |
Asset allocation structure of the portfolio |
Target allocations for fiscal 2016 | 55.00%
Equity securities — international |
Asset allocation structure of the portfolio |
Target allocations for fiscal 2016 | 10.00%
Fixed income |
Asset allocation structure of the portfolio |
Asset allocation structure of the portfolio | 38.00%
Target allocations for fiscal 2016 | 30.00%
Other |
Asset allocation structure of the portfolio |
Asset allocation structure of the portfolio | 1.00%
Target allocations for fiscal 2016 | 5.00%

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