Benefit Plans and Other Postretirement Benefits, Projected Benefit Payments (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013
Pension Plans
Defined Benefit Plan, Gross Projected Benefit Payments [Abstract]
2014	$ 26,265
2015	27,361
2016	27,565
2017	28,738
2018	29,703
2019-2023	153,507
Postretirement Benefit Plan
Defined Benefit Plan, Gross Projected Benefit Payments [Abstract]
2014	3,285
2015	3,450
2016	3,547
2017	3,691
2018	3,582
2019-2023	17,912
Expected Medicare Part D Subsidies [Abstract]
2014	33
2015	36
2016	50
2017	52
2018	55
2019-2023	186
Defined Benefit Plan, Net Projected Benefit Payments [Abstract]
2014	3,252
2015	3,414
2016	3,497
2017	3,639
2018	3,527
2019-2023	$ 17,726

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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).