Income Taxes (Details) (USD $)	3 Months Ended	6 Months Ended
Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011
Income Taxes
Effective income tax rate from continuing operations (as a percent)	(91.50%)	48.20%	(76.90%)	42.50%
Income tax expense (benefit)	$ 29,058,000	$ 1,164,000	$ 28,492,000	$ 7,293,000
Federal statutory tax rate (as a percent)	35.00%	35.00%	35.00%	35.00%
Reconciliation of effective income tax rate to federal statutory tax rate
Valuation allowance against deferred tax assets (as a percent)	(101.00%)		(87.00%)
Write-off of goodwill (as a percent)	(25.00%)		(21.00%)
Stock-based compensation shortfalls (as a percent)			(5.00%)
Cumulative loss position period	3 years
Valuation allowance	32,100,000		32,100,000
Net deferred tax assets	$ 581,000	$ 600,000	$ 581,000	$ 600,000	$ 30,766,000
Reduction in deferred tax assets ( as a percentage)	(87.00%)

Percentage increase/(decrease) of deferred tax asset.

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Represents the period for which the entity is in a cumulative loss position.

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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A ratio calculated by dividing the reported amount of income tax expense attributable to continuing operations for the period by GAAP-basis pretax income from continuing operations.

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- Definition

The domestic federal statutory tax rate applicable under enacted tax laws to the Company's pretax income from continuing operations for the period. The "statutory" tax rate is the regular tax rate if there are alternative tax systems.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate attributable to changes in the valuation allowance for deferred tax assets.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate attributable to nondeductible impairment losses under enacted tax laws.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate attributable to differences in the deductibility or nondeductibility of incentive stock options and other equity-based compensation costs in accordance with generally accepted accounting principles and enacted tax laws.

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The sum of the current income tax expense or benefit and the deferred income tax expense or benefit pertaining to continuing operations.

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-Glossary Income Tax Expense (or Benefit)

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