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Employee Benefits, Defined Contribution Plans Narrative (Details) - Defined Contribution Plan | 12 Months Ended |
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Dec. 31, 2016 USD ($) productionfacilities | Dec. 31, 2015 USD ($)
Hourly bargaining unit employees |  |
Defined Contribution Plan Disclosure [Line Items] |  |
Number of production facilities | 9 |
Hourly bargaining unit employees | Fixed rate contributions |  |
Defined Contribution Plan Disclosure [Line Items] |  |
Number of production facilities | 3 |
Hourly bargaining unit employees | Concurrent match |  |
Defined Contribution Plan Disclosure [Line Items] |  |
Number of production facilities | 1 |
Hourly bargaining unit employees | Fixed rate and concurrent match |  |
Defined Contribution Plan Disclosure [Line Items] |  |
Number of production facilities | 3 |
Hourly bargaining unit employees | No contributions required |  |
Defined Contribution Plan Disclosure [Line Items] |  |
Number of production facilities | 2 |
Salaried and certain hourly employee | Concurrent match |  |
Defined Contribution Plan Disclosure [Line Items] |  |
Defined contribution plan employer concurrent match percentage | 4.00% |
Hired on or after January 1, 2004 | Hourly bargaining unit employees | Fixed rate contributions |  |
Defined Contribution Plan Disclosure [Line Items] |  |
Defined contribution plan annual employer contribution percentage | 2.00% |
Hired on or after January 1, 2004 | Salaried and certain hourly employee | Fixed rate contributions |  |
Defined Contribution Plan Disclosure [Line Items] |  |
Defined contribution plan annual employer contribution percentage | 2.00% |
Minimum | Hourly bargaining unit employees |  |
Defined Contribution Plan Disclosure [Line Items] |  |
Estimated annual contribution to pension and other postretirement benefit plans | $ | $ 1,800,000 | $ 1,900,000
Minimum | Hourly bargaining unit employees | Fixed rate contributions |  |
Defined Contribution Plan Disclosure [Line Items] |  |
Defined Contribution Plan, Employer Discretionary Contribution Amount | $ | 800 |
Minimum | Salaried and certain hourly employee |  |
Defined Contribution Plan Disclosure [Line Items] |  |
Estimated annual contribution to pension and other postretirement benefit plans | $ | $ 7,200,000 | $ 6,700,000
Minimum | Hired prior to January 1, 2004 | Hourly bargaining unit employees | Fixed rate contributions |  |
Defined Contribution Plan Disclosure [Line Items] |  |
Defined contribution plan annual employer contribution percentage | 2.00% |
Minimum | Hired prior to January 1, 2004 | Salaried and certain hourly employee | Fixed rate contributions |  |
Defined Contribution Plan Disclosure [Line Items] |  |
Defined contribution plan annual employer contribution percentage | 2.00% |
Maximum | Hourly bargaining unit employees | Fixed rate contributions |  |
Defined Contribution Plan Disclosure [Line Items] |  |
Defined Contribution Plan, Employer Discretionary Contribution Amount | $ | $ 2,400 |
Maximum | Hired prior to January 1, 2004 | Hourly bargaining unit employees | Fixed rate contributions |  |
Defined Contribution Plan Disclosure [Line Items] |  |
Defined contribution plan annual employer contribution percentage | 10.00% |
Maximum | Hired prior to January 1, 2004 | Salaried and certain hourly employee | Fixed rate contributions |  |
Defined Contribution Plan Disclosure [Line Items] |  |
Defined contribution plan annual employer contribution percentage | 10.00% |

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- Definition Defined Contribution Plan Employer Contribution Percentage + References No definition available. + Details
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- Definition Estimated annual contribution to pension and other postretirement benefit plans. + References No definition available. + Details
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- Definition Number of Production Facilities. + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Amount of discretionary contributions made by an employer to a defined contribution plan. + References No definition available. + Details
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- Definition Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan. + References No definition available. + Details
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