Income Taxes (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Current:
Federal	$ 3,508	$ 3,565
State and local	1,079	1,170
Foreign	(128)	(90)
Total current provision	4,459	4,645
Deferred:
Federal	3,747	3,545
State and local	679	872
Foreign	102	193
Total deferred provision	4,528	4,610
Provision for income taxes	$ 8,987	$ 9,255

Deferred provision income tax expense benefit.

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The component of income tax expense for the period representing amounts paid or payable (or refundable) as determined by applying the provisions of enacted federal tax law to the domestic taxable Income or Loss from continuing operations.

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The component of income tax expense for the period representing amounts of income taxes paid or payable (or refundable) for the period for all income tax obligations as determined by applying the provisions of relevant enacted tax laws to relevant amounts of taxable Income or Loss from continuing operations.

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The component of income tax expense for the period representing amounts paid or payable (or refundable) as determined by applying the provisions of enacted state and local tax law to relevant amounts of taxable Income or Loss from continuing operations.

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The component of total income tax expense for the period comprised of the increase (decrease) during the period in the entity's domestic deferred tax assets and liabilities attributable to continuing operations as determined by applying the provisions of the federally enacted tax law.

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The component of total income tax expense for the period comprised of the increase (decrease) in the entity's net foreign deferred tax assets and liabilities attributable to continuing operations as determined by applying the provisions of applicable enacted tax laws of countries other than the country of domicile.

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The component of total income tax expense for the period comprised of the increase (decrease) in the entity's state and local deferred tax assets and liabilities attributable to continuing operations as determined by applying the provisions of the applicable 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 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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