Benefit Plans and Other Postretirement Benefits, Projected Benefit Payments (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014
Pension Plans
Defined Benefit Plan, Gross Projected Benefit Payments [Abstract]
2015	$ 25,988
2016	27,029
2017	27,674
2018	28,896
2019	29,377
2020-2024	156,430
Postretirement Benefit Plan
Defined Benefit Plan, Gross Projected Benefit Payments [Abstract]
2015	3,166
2016	3,171
2017	3,119
2018	3,034
2019	2,992
2020-2024	14,498
Expected Medicare Part D Subsidies [Abstract]
2015	24
2016	31
2017	32
2018	30
2019	29
2020-2024	153
Defined Benefit Plan, Net Projected Benefit Payments [Abstract]
2015	3,142
2016	3,140
2017	3,087
2018	3,004
2019	2,963
2020-2024	$ 14,345

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The amount of the benefits expected to be paid, net of the prescription drug subsidy receipts expected to be received in the five fiscal years thereafter (the aggregate net amount of benefits expected to be paid in years 6 through 10 after the date of the latest statement of financial position).