Employee Benefits, Defined Contribution Plans (Details) (Defined Contribution Plan, USD $)	12 Months Ended
	Dec. 31, 2014 productionfacilities
Hourly bargaining unit employees
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Number of production facilities	7
Hourly bargaining unit employees | Fixed rate contributions
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Number of production facilities	3
Hourly bargaining unit employees | Concurrent match
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Number of production facilities	1
Hourly bargaining unit employees | Fixed rate and concurrent match
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Number of production facilities	2
Hourly bargaining unit employees | No contributions required
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Number of production facilities	1
Salaried and certain hourly employee | Concurrent match
Deferred Compensation Arrangement with Individual, Postretirement Benefits [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
Deferred Compensation Arrangement with Individual, Postretirement Benefits [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
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Defined contribution plan annual employer contribution percentage	2.00%
Minimum | Hourly bargaining unit employees
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Estimated annual contribution to pension and other postretirement benefit plans	1,000,000
Minimum | Hourly bargaining unit employees | Fixed rate contributions
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Defined contribution plan annual employer contribution	800
Minimum | Salaried and certain hourly employee
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Estimated annual contribution to pension and other postretirement benefit plans	5,000,000
Minimum | Hired prior to January 1, 2004 | Hourly bargaining unit employees | Fixed rate contributions
Deferred Compensation Arrangement with Individual, Postretirement Benefits [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
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Defined contribution plan annual employer contribution percentage	2.00%
Maximum | Hourly bargaining unit employees
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Estimated annual contribution to pension and other postretirement benefit plans	3,000,000
Maximum | Hourly bargaining unit employees | Fixed rate contributions
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Defined contribution plan annual employer contribution	2,400
Maximum | Salaried and certain hourly employee
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Estimated annual contribution to pension and other postretirement benefit plans	7,000,000
Maximum | Hired prior to January 1, 2004 | Hourly bargaining unit employees | Fixed rate contributions
Deferred Compensation Arrangement with Individual, Postretirement Benefits [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
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Defined contribution plan annual employer contribution percentage	10.00%