Pension and Other Postretirement Benefits (Details) (USD $)	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Pension and Other Postretirement Benefit Expense [Abstract]
Pension curtailment gain recognized	$ 12,000,000
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Contribution to pension and other postretirement benefit plans during period			55,400,000
Expected additional contribution to pension and other postretirement benefit plans for the year	1,000,000		1,000,000
Pension Plans, Defined Benefit [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	3,142,000	4,013,000	9,323,000	11,907,000
Interest cost	7,802,000	7,822,000	23,152,000	23,211,000
Expected return on plan assets	(8,445,000)	(7,695,000)	(25,058,000)	(22,833,000)
Recognized actuarial (gain) loss	(7,221,000)	5,357,000	4,294,000	15,978,000
Amortization of prior service cost	(1,684,000)	(1,683,000)	(4,996,000)	(4,995,000)
Total net pension and postretirement benefit cost	(6,406,000)	7,814,000	6,715,000	23,268,000
Less: Discontinued operations	(11,450,000)	3,473,000	(6,855,000)	10,990,000
Total net pension and postretirement costs from Continuing operations	5,044,000	4,341,000	13,570,000	12,278,000
Other Postretirement Benefit Plans, Defined Benefit [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	547,000	595,000	1,623,000	1,767,000
Interest cost	1,064,000	1,160,000	3,158,000	3,442,000
Recognized actuarial (gain) loss	75,000	98,000	221,000	293,000
Amortization of transition obligation	167,000	167,000	495,000	495,000
Amortization of prior service cost	(52,000)	(51,000)	(153,000)	(153,000)
Total net pension and postretirement benefit cost	1,801,000	1,969,000	5,344,000	5,844,000
Less: Discontinued operations	399,000	556,000	1,618,000	1,919,000
Total net pension and postretirement costs from Continuing operations	$ 1,402,000	$ 1,413,000	$ 3,726,000	$ 3,925,000

This is a combination of two elements-postretirement benefits claims paid and contributions to pension plans.

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Net increase or decrease in the plan benefit obligation from continuing operations during the reporting period.

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The net increase or decrease of changes in the value of either the benefit obligation or the plan assets resulting from experience different from that assumed or from a change in an actuarial assumption, or the consequence of a decision to temporarily deviate from the substantive plan.

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The amounts in accumulated other comprehensive income related to transition assets (obligations), origination from the adoption of FAS 87 and 106, expected to be recognized as components of net periodic benefit cost over the next fiscal year that follows the most recent annual statement of financial position presented.

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The amount of the prior service cost or credit recognized in net periodic benefit cost relating to benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation.

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Net increase or decrease in the plan benefit obligation during the reporting period.

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The amount of decrease in the plan benefit obligation attributed to the sale, liquidation, spin-off or other divestiture of a corporate division or subsidiary.

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The employer's best estimate, as soon as it can be reasonably determined, of contributions expected to be paid to the plan in the current remaining fiscal period. Estimated contributions may be presented in the aggregate combining (1) contributions required by funding regulations or laws, (2) discretionary contributions, and (3) noncash contributions.

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An amount calculated as a basis for determining the extent of delayed recognition of the effects of changes in the fair value of assets. The expected return on plan assets is determined based on the expected long-term rate of return on plan assets and the market-related value of plan assets.

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The amount of net gain (loss) recognized in net periodic benefit cost as a result of an event that significantly reduces the expected years of future service of present employees or eliminates for a significant number of employees the accrual of defined benefits for some or all of their future services.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.

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