Condensed Consolidated Statements of Comprehensive Income (unaudited) (USD $) In Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Condensed Consolidated Statements of Comprehensive Income (unaudited) [Abstract]
Net earnings	$ 10,785	$ 8,493	$ 29,269	$ 23,861
Other comprehensive income, net of tax where applicable:
Translation adjustments	(675)	845	143	(174)
Unfunded postretirement benefit plan	(2)	(3)	(5)	(10)
Comprehensive income, net of tax where applicable	$ 10,108	$ 9,335	$ 29,407	$ 23,677

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 reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

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- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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+ Details

- Definition

The accumulated change in the value of either the projected benefit obligation or the plan assets resulting from experience different from that assumed or from a change in an actuarial assumption that has not been recognized in net periodic benefit cost, after tax.

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Adjustment that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency of the reporting entity, net of tax.

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