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	$ 77,490
2015	78,297
2016	80,894
2017	81,037
2018	84,004
2019-2023	430,547
Postretirement Benefit Plan
Defined Benefit Plan, Gross Projected Benefit Payments [Abstract]
2014	36,778
2015	38,061
2016	39,418
2017	40,135
2018	42,019
2019-2023	206,729
Expected Medicare Part D Subsidies [Abstract]
2014	2,396
2015	2,564
2016	2,715
2017	2,881
2018	3,042
2019-2023	17,204
Defined Benefit Plan, Net Projected Benefit Payments [Abstract]
2014	34,382
2015	35,497
2016	36,703
2017	37,254
2018	38,977
2019-2023	$ 189,525

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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).