Changes in Equity and Comprehensive Income Changes in Equity and Comprehensive Income (Details of Accumulated Other Comprehensive Income Components) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Income Tax Expense (Benefit)	$ (26,758)	$ (27,112)	$ (49,647)	$ (49,864)
Amounts reclassified from accumulated other comprehensive income			2,312
Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	(1,164)	(3,689)	(2,359)	(6,753)
Income Tax Expense (Benefit)	360	1,211	47	2,171
Amounts reclassified from accumulated other comprehensive income	(804)	(2,478)	(2,312)	(4,582)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Prior-Service Costs, Pension [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
PriorServiceCostsCOS	40	18	81	9
PriorServiceCostSG&A	(10)	(5)	(21)	(2)
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)	30	13	60	7
Reclassification out of Accumulated Other Comprehensive Income [Member] | Net Loss (Gain), Pension [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Defined Benefit Plan, Amortization of Gains (Losses)	(1,257)	(3,723)	(2,514)	(6,887)
NetlossgainCOS	1,704	5,046	3,407	9,344
NetlossgainSG&A	(447)	(1,323)	(893)	(2,450)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Prior-Service Costs, Postretirement [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)	(56)	(59)	(115)	(118)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Net Loss(Gain), Postretirement [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Defined Benefit Plan, Amortization of Gains (Losses)	$ 67	$ (12)	$ 100	$ 23