Equity Comprehensive Income (Details) (USD $) In Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Dec. 31, 2010
Prior service cost	$ (764)		$ (764)		$ (853)
Transition asset	276		276		324
Unrecognized net actuarial loss	(5,491)		(5,491)		(5,678)
Net income	45,109	38,763	131,485	105,411
Amortization of deferred pension costs, net of tax	76	86	228	257
Total comprehensive income	45,185	38,849	131,713	105,668
Total accumulated other comprehensive income (loss)	$ (5,979)		$ (5,979)		$ (6,207)

Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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- Definition

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the economic entity, including both controlling (parent) and noncontrolling interests. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, including any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

+ References+ Details

- Definition

Amount related to the pretax cost of benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation, which has not yet been recognized as components of net periodic benefit cost.

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- Definition

Of the original amount of transition assets as of the date FAS 87 or 106 was initially applied, (a) the fair value of plan assets plus any recognized accrued pension or other postretirement benefit cost or less any recognized prepaid pension or other postretirement benefit cost in excess of (b) the benefit obligation, the portion of which has yet to be recognized as components of net periodic benefit cost. Of the original amount of transition obligations as of the date FAS 87 or 106 was initially applied, (a) the benefit obligation in excess of (b) the fair value of plan assets plus any recognized accrued pension or other postretirement benefit cost or less any recognized prepaid pension or other postretirement benefit cost, the portion of which has yet to be recognized as components of net periodic benefit cost. This amount is pretax.

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- Definition

The adjustment out of other comprehensive income for prior service costs recognized as a component of net period benefit cost during the period, after tax.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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