Income Taxes (Details 2) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Components of income tax expense (benefit), continuing operations
Income tax expense (benefit) at U.S. federal statutory rate	$ 5,310	$ (22,250)	$ (32,948)
State and local income taxes, net of federal income tax benefit	958	(4,945)	(636)
Book expenses not deductible for tax purposes	746	662	816
Stock-based compensation	464	518	(3,534)
Amortization of non-deductible goodwill	1	3	6
Undistributed earnings of Canadian subsidiaries (a)	(4,023)	1,083	828
Valuation allowance	382	1,487	(9)
Rate Change (b)	1,743
Other differences, net	1,042	(27)	(624)
Income tax expense (benefit)	$ 6,623	$ (23,469)	$ (36,101)

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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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The sum of the differences between total income tax expense or benefit as reported in the Income Statement for the period 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 nondeductible expenses under enacted tax laws, or differences in the methodologies used to determine expense amounts for financial statements prepared in accordance with generally accepted accounting principles and enacted tax laws.

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