Employee Benefits, Defined Contribution Plans Narrative (Details)	12 Months Ended
Dec. 31, 2018 USD ($) productionfacilities
Defined Contribution Plan Disclosure [Line Items]
Equity Securities, FV-NI, Unrealized Gain (Loss) \| $	$ (1,000,000.0)
Defined Contribution Plan \| Hourly bargaining unit employees
Defined Contribution Plan Disclosure [Line Items]
Number of production facilities	9
Defined Contribution Plan \| Hourly bargaining unit employees \| Fixed rate contributions
Defined Contribution Plan Disclosure [Line Items]
Number of production facilities	3
Defined Contribution Plan \| Hourly bargaining unit employees \| Concurrent match
Defined Contribution Plan Disclosure [Line Items]
Number of production facilities	1
Defined Contribution Plan \| Hourly bargaining unit employees \| Fixed rate and concurrent match
Defined Contribution Plan Disclosure [Line Items]
Number of production facilities	3
Defined Contribution Plan \| Hourly bargaining unit employees \| No contributions required
Defined Contribution Plan Disclosure [Line Items]
Number of production facilities	2
Defined Contribution Plan \| Salaried and certain hourly employee \| Concurrent match
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plan employer concurrent match percentage	4.00%
Defined Contribution Plan \| 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%
Defined Contribution Plan \| 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%
Defined Contribution Plan \| Minimum \| Hourly bargaining unit employees \| Fixed rate contributions
Defined Contribution Plan Disclosure [Line Items]
Defined Contribution Plan, Employer Discretionary Contribution Amount \| $	$ 800
Defined Contribution Plan \| 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%
Defined Contribution Plan \| 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%
Defined Contribution Plan \| Maximum \| Hourly bargaining unit employees \| Fixed rate contributions
Defined Contribution Plan Disclosure [Line Items]
Defined Contribution Plan, Employer Discretionary Contribution Amount \| $	$ 2,400
Defined Contribution Plan \| Maximum \| Salaried and certain hourly employee
Defined Contribution Plan Disclosure [Line Items]
Estimated annual contribution to pension and other postretirement benefit plans \| $	$ 2,900,000
Defined Contribution Plan \| 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%
Defined Contribution Plan \| 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%

Defined Contribution Plan Employer Contribution Percentage

No definition available.

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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

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+ References

No definition available.

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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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- Definition

Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=84241550&loc=SL75117546-209714

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