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	$ 16,388
2014	15,152
2015	16,117
2016	14,986
2017	14,664
2018-2022	69,528
Postretirement Benefit Plan [Member]
Defined Benefit Plan, Gross Projected Benefit Payments [Abstract]
2013	1,598
2014	1,468
2015	1,459
2016	1,433
2017	1,365
2018-2022	6,286
Expected Medicare Part D Subsidies [Abstract]
2013	8
2014	11
2015	9
2016	8
2017	3
2018-2022	16
Defined Benefit Plan, Net Projected Benefit Payments [Abstract]
2013	1,590
2014	1,457
2015	1,450
2016	1,425
2017	1,362
2018-2022	$ 6,270

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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).