Benefit Plans and Other Postretirement Benefits, Projected Benefit Payments (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Pension Plans [Member]
Defined Benefit Plan, Gross Projected Benefit Payments [Abstract]
2013	$ 24,684
2014	26,123
2015	26,660
2016	26,715
2017	28,019
2018-2022	146,565
Postretirement Benefit Plan [Member]
Defined Benefit Plan, Gross Projected Benefit Payments [Abstract]
2013	3,271
2014	3,363
2015	3,643
2016	3,758
2017	3,832
2018-2022	18,239
Expected Medicare Part D Subsidies [Abstract]
2013	32
2014	38
2015	42
2016	51
2017	56
2018-2022	210
Defined Benefit Plan, Net Projected Benefit Payments [Abstract]
2013	3,239
2014	3,325
2015	3,601
2016	3,707
2017	3,776
2018-2022	$ 18,029

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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).