Income Taxes (Details 2) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Differences between the income tax provisions and the provisions for income taxes
Expected tax at statutory rate	$ 7,377	$ 8,775	$ 4,560
Foreign taxes at other rates	(2,513)	(1,758)	(1,642)
Change in valuation allowance due to:
NOL valuation reserve adjustments		(1,639)	(335)
Utilization of NOL carryforwards	(43)	(4,873)	(725)
Generation of NOL carryforwards		134	157
Prior year tax adjustments	(19)	171	67
Other, net	666	747	524
Total	$ 5,468	$ 1,557	$ 2,606

The sum of the current income tax expense or benefit and the deferred income tax expense or benefit pertaining to pretax Income or Loss from continuing operations; income tax expense or benefit may include interest and penalties on tax uncertainties based on the entity's accounting policy.

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to changes in the valuation allowance for deferred tax assets in the period.

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